Here is an Instructable for making some deliciously gory, fudgy hands perfect for your Halloween party.

Step 1: Gather Ingredients and Tools

Software:

2 Cans of Sweetened Condensed Milk
1 Lb of either chocolate or vanilla bark. (Milk chocolate, white chocolate, and chocolate chips will work fine.)
1 small container of red gel food coloring
1 small container of peach gel food coloring (optional)

Hardware:
1 or 2 Hand shaped Jello molds. (Or any other mold you'd like to try.
Large pot and lid for boiling. (The larger, the better)
Spatulas (Silicon is best)
Parchment paper
Aluminum Foil
A few spoons
Large knife and cutting mat (If using large block of chocolate.)
Can opener
Long tongs or something to remove a hot can from boiling water
Unpowdered Latex Gloves (optional)
Vegetable steamer basket (optional)

Step 2: Early Work: Dulce De Leche

Our first step is to prepare our dulce de leche filling for the fudge. For those who are unfamiliar with this treat, it taste very much like a gooey, creamy caramel.

This step will take hours to complete, but luckily you can do this several weeks in advance. Since it is just as easy to prepare four cans as one, I tend to do them in large batches so that I already have them available when I want to use them. (It's great on ice cream, and even better on top of S'Mores.)

There are many sources for instructions on how to make dulce de leche, including here at Instructables, but I'll walk you through the simple steps that I've been using for years.

For this recipe we are going to do one can thin, and optionally one can thick.

First, take all of the cans you are going to prepare, and discard the labels.
Put the cans in the tallest pot you can find and fill it with water. If you pot is very large or awkward to carry when it is full, I recommend putting it on the stove, and then using a pitcher with hot tap water to fill it. Cover and boil, checking back periodically to make sure the water level stays at least an inch above the top of the cans. The longer you boil the cans, the thicker the dulce de leche will be. For the blood, we need it a little thinner, so 4-5 hours should be fine. Carefully use tongs or something else to pull them out of the water . Optionally, you can use thick dulce de leche in the fudge, if you want to do this, I recommend cooking it for 8 hours to get it nice and thick.

After your cook time is up, remove the lid and turn off the heat. You can leave the thick can in the water for extra time (even over night) to let them cook longer, and cool of their own. Or use the large tongs again to fish them out and let them cool on the counter. Let them cool until they are no longer too hot to handle before opening. Be careful, if you attempt to open them when they are too hot, scalding hot sugar will quickly ooze out of the can.

Tip: If your pot is deep enough, put a steamer basket in the bottom first, and then place your cans on top of it. This will help prevent parts of the dulce de leche from burning inside the can due to conduction with the bottom of the pot.

Step 3: Make the Blood

Now that you have dulce de leche made, it is time to bloody it up a little bit.

We are using icing coloring instead of food coloring here so that we can get a darker color without changing the consistency of the "blood." We got ours at Michael's arts and crafts, but you should be able to find it in any craft shop or baking store.

Slowly shake, pour, or spoon some of your red coloring into your thin dulce de leche. Add a little bit at a time, and then mix it up until you find just the color you are looking for. We used a little less than a quarter of our bottle to get the red color we wanted.

This should be enough blood to fill 3-4 hands plus some extra for pouring around the plate.

Step 4: Preparing the Chocolate

In this and following steps I will refer to both chocolate, white chocolate, and vanilla bark as just chocolate.

If you are using a large block of chocolate, use a large knife to chop it down into smaller manageable pieces. Start chopping and scraping around the edges and work your way in. Try to get most of the piece about the same size.

Now, put your chopped chocolate or chocolate chips in a large microwavable bowl and heat it in the microwave for 30 seconds. Remove and stir. Microwave again for 20 seconds, and then stir again. Continue to nuke for 20 and stir until the chocolate has fully melted. It took me 4 or 5 times to get all of my chocolate melted evenly this time.

Don't be tempted to heat it for longer without stirring. Your chocolate will heat unevenly, and will likely burn.

Step 5: (Optional) Make Some Bones

This step is optional, but I believe it adds a great deal to the finished product.

If you melted while chocolate in the previous step, you can use some of it now to make the bones. If not, melt a small amount of white chocolate in the microwave using a similar procedure as before, but for 15 second intervals this time.

Lay a sheet of parchment paper on the counter. Now, using a spoon dip out a small amount of the white chocolate. Pour it in a thin line going back and forth the length of your mold's fingers. Don't worry too much if it spreads out, you can always trim away the excess later. Repeat this for all five fingers. (10 fingers if you are doing both hands.)

Now, make some other small circles and shapes to represent other bones in the hand. Do two small circles to fit on the end of the wrist for the Ulna and the Radius bones.

Set these aside to harden. It shouldn't take more than a minute or so, but if you would like to speed up the process try setting them on a flat surface in the refrigerator.

Step 6: Making the Fudge

Now, to the melted chocolate, add the can of the thicker dulce de leche or just a regular can of sweetened condensed milk. Stir this until completely combined. The dulce de leche version will set thicker. If it becomes too thick to stir, microwave it for 15 seconds and resume stirring.

If you want to add the peach food coloring, add it during this time. Start off with just a drop and add more as needed. It took much less peach to color our chocolate than it did red to color the blood.

Step 7: Molding - Layer 1

Your fudge should be a thick enough that if you press down on it with a spoon it leaves an indention. If not, left it sit for a few minutes to cool down and warm up.

Coat this inside of your mold heavily with no-stick spray. Pay special attention to the fingers, this is where the most problems occur with the fudge getting stuck.

Using a spoon or spatula, scoop some of the chocolate into mold. Fill it about half way, covering most of the fingers. Press down on the fudge using either latex gloves or a scrap piece of parchment paper. Try to get as many of the gaps and air bubbles out as possible.

Step 8: Molding - Filling

If you made bones, go get them ready .

Now, using either the gloves or parchment paper try to make some hollow pockets in the hand and fingers. Push the fudge up onto the side of the mold to make a small bowl in the palm. Try to keep some parts of the fudge high enough so that they will not be completely covered with the blood filling.

Push the bones into the fudge in the appropriate places in the hand. Don't push them all the way through.

Now, slowly spoon in a small amount of the blood filling. Fill the cavities you made, but try not to get any on the side. You need to have enough of the first layer of fudge exposed so that the top layer of fudge has something to hold onto. I filled a few small pocket in the hand and just did small strings of blood near the bones of the fingers.

Step 9: Molding - Layer 2

Take some of the remaining fudge and scoop it into the mold until it is full. Lightly press down using some parchment paper to smooth it out and stick the top and bottom layers.

Wrap the whole mold in aluminum foil. Prop up the mold level by either using a towel, or by setting it in an appropriately size bowl. Let this set for at least 3 hours. (If you would like to speed this up, once again, you can use the refrigerator.

Step 10: Unmolding

Once your fudge has firmed up a bit, it is time to unmold it.

Depending on your mold and how thick your fudge is, this may be the most difficult part. Stretch the sides of the mold a bit to loosen as much of the fudge as possible. Hopefully, most of the sides will come free with relative ease. Lay the mold, fudge side down, onto a sheet of parchment paper. Slowly push down on the back of the hand and near the fingers of the mold to get the fudge to come out.

If some of your fudge gets stuck, don't fret too much. This is a mangled, severed hand after all. Any holes or missing fingers can be touched up later. (The fudge for my first hand was too thin, and the fingers were mangles during demolding. The finished product still had an amazing effect on the people who saw it.)

Step 11: Finishing

Time to add the finishing touches.

Using a small amount of melted chocolate, or some blood, stick the 2 bones onto the wrist of the hand.

Any mangled parts of the hand can be repaired by remolding the fudge by hand, or using the extra blood to cover the tears in the fudge. Spoon extra blood around the plate for added effect.

Serve with a large knife or meat cleaver and enjoy.