Introduction: Irish Coffee Filled Chocolates

About: I'm a biologist interested in all things sciency. I love to figure out how things work and to make my own stuff, be it food, woodworking, electronics or sewing.

This is a chocolate version of the classic Irish Coffee.
For those who don't know, Irish coffee is coffee with whisky and whipped cream. We are using a dark chocolate ganache with coffee and whisky in a delicious white chocolate shell.

Step 1: What You'll Need

Tools:
Glass bowl or pot for melting chocolate.
Kettle
Spatula
Scraper
Chocolate mold

Instant read thermometer

Piping bag

A marble plate or stone counter top is handy to have, but no requirement.
A teflon sheet makes a good substitute, and you can get by with baking sheets.

A sous vide circulator or water bath is great for keeping the chocolate at working temperature if you have one.

Ingredients

Filling:
250 g chocolate
1 dl whipping cream
5 cl whisky
2 tea spoons of instant coffee
40 g honey

For the shells, you will need about 1kg of white chocolate. You are not going to use all of it, but smaller amounts are hard to work with. What is left afterwards can be used in other projects later on.

Step 2: Choosing Chocolate

When choosing your chocolate, look for a good quality one. It should have few ingredients. A good quality chocolate should only contain cocoa, cocoa butter, milk powder, sugar and usually some vanilla. Lower qualities of chocolate typically replaces the cocoa butter with something else, as cocoa butter fetches higher prices in cosmetics than in food.

It is possible to buy what is called no temp chocolate. Here, the cocoa butter is replaced with other fats that don't need tempering. These chocolates are easy to work with, but they frankly don't taste nice, so go for the good stuff.

White chocolate contains mainly cocoa butter, and no cocoa powder. This gives it a low melting point, and makes it a bit more challenging to work with than dark chocolate.

Step 3: Irish Coffee Ganache

Start with chopping up the chocolate. This makes it easier to melt later on. The finer it is chopped, the faster it is going to melt. If you buy chocolate drops, just use them as they are.

Add two teaspoons of instant coffee to the cream and bring it to a boil. Remove the cream from the heat and add the honey. Stir until the honey is dissolved, and pour the warm mixture over the chocolate. Stir until the chocolate is melted. Stirr in the whisky. Use a spatula for stirring and not a whisk, as we dont want a lot of air bubbles in the filling.
If the heat of the cream is not enough to melt the chocolate, just put the bowl over a kettle of warm water while you keep stirring to melt the rest.

Now set the ganache aside to cool. Leave it in room temperature to ensure it stays soft enough to be used in a piping bag. This is a soft ganache, not suitable for making rolled truffles from. The taste should be quite strong, as it will be dampened by the mild white chocolate in the finished product.

Step 4: Temper the Chocolate

Time for some chocolate science.

When making filled chocolates, tempering it correctly is of vital importance.

So, what is tempering?


The cocoa fat in chocolate can form six types of crystals when it solidifies. In chocolate making, we want to select for just the right kind.

Why is the crystal type important?

Think of carbon as an example. Both diamonds and pencil lead graphite are pure carbon, but the crystal types are different. If you want to make a nice engagement ring, choosing the right crystal type of carbon is important.

Correctly tempered chocolate gets a nice and shiny surface when it solidifies, does not melt that easily in your hands, and has a nice snap when you bite it.

Below is an overview of the melting temperatures and properties of the different chocolate crystal types. These are generalised temperatures, as the other constituents of the chocolate will also affect when crystals form.

If you buy professional quality chocolates, these usually come with tempering instructions.

Crystal Melting Temperature Notes

I 17°C (63°F) Soft, crumbly, melts too easily.

II 21°C (70°F) Soft, crumbly, melts too easily.

III 26°C (78°F) Firm, poor snap, melts too easily.

IV 28°C (82°F) Firm, good snap, melts too easily.

V 34°C (94°F) Glossy, firm, best snap, melts near body temperature (37°C).

VI 36°C (97°F) Hard, takes weeks to form.

When we are making chocolate, we are looking for crystal type V.


Tempering involves three main steps

- First we heat the chocolate to make sure all the cocoa butter crystals are melted. In our case with white chocolate, that means heating it to between 40 and 45°C. If we let it cool down until it solidifies at this point, we are going to get a mix of crystal types, and the chocolate is going to be ugly, crumbly and melt easy. The easiest way to do this is to do it over warm water. I don't say water bath, as the water should not actually touch the container with the chocolate. You just want the heat it is giving of. The water should just be warm, and not boil. Keep stirring the chocolate all the time, even if it is still solid. White chocolate can retain its shape even if it is completely melted. The stirring is also important to keep the chocolate from burning.

- Next, we need to cool it down to allow crystals to start forming. For white chocolate, that means cooling it to 27°C. My preferred way of doing this is by what is called seeding. That means I'm adding chopped chocolate to the warm chocolate a little at a time. This addition of room tempered chocolate is going to cool down the molten chocolate as it too melts. This has the additional benefit that the chocolate you are adding is already tempered by the manufacturer, and these crystals will help the crystallisation of your chocolate, hence the term seeding. The cooling should be quite fast. As a rule of thumb, it should not take more than 10 minutes per kg of chocolate.

As you can see from the list above, adding more chocolate when the temperature is below 34 degrees is going to leave a lot of unmelted pieces, as the crystals will no longer melt. To cool it down the last few degrees, I usually use a cold water bath. You need to stir the chocolate constantly during the tempering to ensure the temperature is even and to keep unwanted crystals from forming. If you cool down the chocolate without the seeding, it is stil going to work, but it will take a lot longer to solidify.

- Now that we have achieved a temperature of 27°C, we need to heat the chocolate a bit again. There are two reasons for doing this. The first is that during our cooling, we have allowed type IV crystals to start forming, and we want to remelt those. The second reason is that we want the chocolate to be as fluid as possible to make it easy to work with. For white chocolate, I reheat it to 30°C. In this step, you have to be really careful not to heat the chocolate to much. If you do, you are going to melt the type V crystal seeds you have been working up to, and you have to start the tempering process again. I keep the chocolate at the working temperature in a water bath heated by a sous vide circulator. To keep it fluid, you have to give it a vigorous stirring now and then, as type V crystals are going to form at this temperature. Be really careful not to get water in your chocolate, as that will ruin it beyond repair.

Now it is time to check your chocolate. Dip the tip of a spatula or a knife in the chocolate, or spread a little on the marble plate or teflon sheet. The chocolate should solidify in about five minutes, and have a shiny surface. If this takes significantly longer, or the chocolate does not go shiny, you should start the tempering process again.

Not tempering the chocolate correctly is no disaster, Chocolate is forgiving, and you can remelt it as many times as you like.

Working with incorrectly tempered chocolate could be a disaster though. One of the properties of correctly tempered chocolate is that it shrinks as it hardens. As it does, it lets go of the molds, and removing it only requires turning the mold upside down. Incorrectly tempered chocolate does not shrink properly, and the only way of removing it from the mold may be to melt it again.

Step 5: Coat Molds

Now that the chocolate is ready, it is time to give our molds a good coating.

I use hard plastic molds that are a lot easier to work with than the soft ones typically sold in kitchen stores.

The molds should be kept at room temperature before use. Don't put them in the fridge, as this will make the chocolate solidify too quickly and give you ugly results.

The first step is to fill the mold completely with chocolate and scrape of the excess. Next, hold the mold on the edge of the bench, so that half the mold is on the bench, and the other half outside it. Rattle the mold up and down a few times to remove air bubbles from the chocolate.

When the chocolate has been in the mold for about 20 seconds, turn the mold around to pour it out. Chocolate is very viscous, and most of it will remain in the molds even when you turn them. To get it moving, use the handle of the spatula to tap the side of the mold. I usually do this over a teflon sheet, as my melting pot is not large enough to hold the mold over. If you are quick, you can scrape up the molten chocolate and put it back in the pot before it gets too cold.

When the chocolate stops running, scrape the top of the mold clean with the spatula while you are stil holding it upside down.

Set the mold down on the marble plate or teflon sheet upside down to solidify. This will help you get even shells on your chocolates. If you set the molds right side down, your chocolate shells are going to be thick in the top, and thin around the bottom edge.

With correctly tempered chocolate the solidifying should only take a few minutes. If you are using a marble plate, you will probably need to give the mold a little tap on the side with the handla of your spatula to make it let go of the plate. Don't pull upwards as that could pull the chocolate shells out of the mold.

Step 6: Fill the Chocolates

With the chocolate shells done, we are ready for the filling.

Transfer the ganache to a piping bag. If it is to solid to pipe easily, work the piping bag in your hands for a while to make it softer. Warming it with the heat of your hands ensures it doesn't get warm enough to melt the shells.

Fill the shells, but make sure to leave a little space for the bottom of the shell. If you fill the chocolates all the way to the edge, you are going to get holes in the bottom. When you have filled the shells, put the mold in the fridge to solidify the ganache. 30 minutes should be plenty of time for this.

Remove the mold from the fridge and cover it with chocolate. Scrape of the excess chocolate, and rattle the mold on the edge of the bench as before to remove air bubbles. As the mold is now fridge cold, some of the chocolate is going to solidify instantly on it. Don't worry about this, and just leave it for now.

Put the mold back in the fridge. You need the low temperature of the fridge to make the chocolate shrink and let go of the molds. This can take a while, and if you are not in a hurry you can just leave it over night.

One detail worth mentioning is that chocolate absorbs flavours fast. Keeping it in the same fridge as garlic, strong smelling cheese or the likes could give you some odd chocolate flavours.

If you are done for the day, spread the rest of the molten chocolate thin on a marble plate or teflon sheet. When it solidifies, you can break it up into little pieces and use it next time.

Step 7: Demold

After waiting patiently, you are now ready to remove the chocolates from the molds. When you look at the molds, you can easily see if the chocolate has let go of the plastic. If you have left it over night and the chocolate still clings to the mold, then it is not going to shrink any further. If it is correctly tempered, this should not happen.

At this point, you probably still have some chocolate on the mold surface, and your chocolate bottoms are not completely flat. Use a metal scraper to remove the excess chocolate and cut the bottoms flush with the mold. Be a bit careful when you do this, as the chocolates should now be loose.

Flip the mold upside down, and the chocolates should come out. If some are still clinging to the mold, give it a few taps.

Your chocolates are now ready to be enjoyed. Kept in a cool place they will keep for a couple of months.

The fridge is not a good place for storing chocolates because of all the varying odours present. The best place is a cool room in the house. The chocolates will also taste better if they are not fridge cold.

Wash the molds with warm water before you store them, but leave the soap. Leaving a thin layer of cocoa butter in the molds makes them easier to work with.

Step 8: What Went Wrong?

Working with chocolate can be a bit tricky, but once you get the hang of it, it's quite easy. Here, I'll list some common problems with causes and solutions.

Chocolate is not shiny/has matte stripes.

This means it was not tempered correctly, and you have got a variety of different crystals. If you have not filled the chocolates, you can simply remelt it and try again. If you have made filled chocolates, you can still eat them. They are going to taste pretty much the same, but the texture might be a bit different.If you rigorously followed the tempering scheme, try with a different thermometer next time.

Molten chocolate solidifies and goes gritty, even if the temperature is unchanged.

This is a sign of water in your chocolate. Just a single drop can ruin a batch. This is the reason why professionals use water free chocolate melters. These are quite expensive, so the rest of us just have to be very careful. If you are unlucky and get water in your chocolate, it is ruined as a covering chocolate, but can still be used to make fillings or for baking.

Chocolate goes to thick to work with, even if the temperature is unchanged.

This can happen if you don't stir it enough. If you let it sit untouched in the water bath, crystals will form. You might manage to get it more fluid again with some vigorous stirring, but if this does not work, heat is the only option. Try heating it just a degree or two and see if that works. Test the temper of the chocolate as before by spreading a little of it on a cool surface. If everything looks all right, you can keep working.

Chocolates will not come out of the molds

If you have been waiting for hours, and the chocolates still cling to the molds, the chocolate was most likely not tempered correctly and there is not much you can do to fix it. This can also happen with correctly tempered chocolate if it is the first time you use the molds, or if you have washed the molds with soap since the previous use. Washing them in just warm water leaves a thin coating of cocoa butter that helps release the chocolates.