How to make homemade vanilla cupcakes with a chocolate German buttercream(or regular German buttercream). This was a test of German Buttercream, something I had never heard of until a couple of weeks ago. There are actually 6 different types of buttercream; German Buttercream(this is a custard based buttercream), Italian Meringue Buttercream(this is meringue-based buttercream that does not require cooking the egg yolks in a double boiler, they are cooked as a hot simple syrup is poured into them), Swiss Meringue Buttercream(this is a meringue-based buttercream that consists of cooking the egg whites over a double boiler with sugar and cream of tartar, also known as potassium hydrogen tartrate, with formula K C₄ H₅ O₆), French Buttercream(this is an egg yolk based buttercream), Ermine Buttercream(this is a rue based buttercream, if you are familiar with making homemade macaroni and cheese, you already know what a rue is, but basically what a rue is mixture of flour and milk(and sometimes butter) and it is used as a thickener to help well thicken sauces like gravy or cheese sauce), and American Buttercream(this is a basic buttercream made with just butter powdered sugar, milk, and a flavoring extract, this is usually used on birthday cakes and has a very sweet buttery flavor)
The cupcake has a very sweet butter flavor with a very light and fluffy texture. The German buttercream is very tasty, it isn't very sweet so if you really like sweet things, I wouldn't recommend this, but all in all, it is a very delicious frosting.
Step 1: Separate Eggs for Custard
Ingredients For The Custard:
1 cup milk
3/4 cup granulated sugar
1 1/2 Tbls. cornstarch
1 1/2 Tbls. flour
2 Tbls. cocoa powder (if you chose to do chocolate)
1.) Separate eggs. You will only need the egg yolks for this recipe, so you can save the egg whites for a later recipe, like a meringue, or throw them away.
Step 2: Add in Rest of Ingredients
2.) Pour in the milk, cocoa powder, cornstarch, sugar, and flour. You can exclude the cocoa powder if you would like to try a plain vanilla German buttercream, or would just prefer a vanilla on vanilla cupcake.
Step 3: Whisk Together
3.) Whisk together until completely combined and appears slightly frothy. So, what exactly is happening here? As the liquid custard mixture is whisked, the mechanical action causes its proteins to unfold and form a network, trapping air in tiny pockets. This creates the froth that is on top of the liquid custard mixture.
Step 4: Transfer Mixture Into Pan
4.) Transfer the custard mixture into a pan over medium-high heat.
Step 5: Heat Until Thickened
5.) Heat on medium-high until thickened, continually stirring. It should become the consistency of a chocolate pudding. The cornstarch and flour are starches and as they heat up they will react with the rest of the custard ingredients and make it thicken, so these are vital ingredients.
Step 6: Strain Custard
6.) Strain the custard through a fine-mesh strainer to remove any pieces of curdled egg that may have developed in the custard while on the heat, and transfer custard to a clean bowl.
Step 7: Top With Cling Film and Store in Fridge
7.) Top with cling film. Be sure to press the cling film against the custard to prevent it from creating a skin on the top. What happens is the top of custard comes in contact with the oxygen in the air, and begins to create a rubbery texture on top, by pressing the cling film on to the custard, you lock out oxygen in the air and prevent this reaction from happening. Now, store the custard in the fridge until it has completely cooled, this could be from 2-3 hrs all the way up to overnight, depending on your fridge setting.
Step 8: Bring Cupcake Ingredients to Room Temperature
Ingredients for Vanilla Cupcakes:
1/2 cup butter
2 egg yolks
1 vanilla bean, split lengthwise, or 1 teaspoon vanilla extract (I used imitation vanilla extract because it was cheaper and we already had some, but I look forward to experimenting with vanilla beans and pure vanilla extract)
1 1/2 cups all-purpose flour
1 1/2 teaspoons baking powder
1/4 teaspoon salt
3/4 cup granulated sugar
1/2 teaspoon vanilla extract
1/2 cup whipping cream
1.) Allow butter, egg, egg yolks, and whipping cream to come to room temperature. Now a lot of people have asked what temperature is room temperature. Room temperature is taken to be about 20 to 25 degrees Celsius with an average of 23 °C (about 73.4 degrees Fahrenheit (°F), 528 to 537 degrees Rankine (°R), or 293 to 298 kelvins (K)). For numerical convenience, either 20 °C or 300 K is often used.
2.) (If using vanilla extract, ignore this step) Using a small sharp knife, cut the vanilla bean in half. Using the back end of the knife, scrape the seeds of the vanilla bean halves and put them in a small bowl, and they will be added to the batter later.
Step 9: Whisk Dry Ingredients
3.) Whisk together the flour, baking powder, and salt until completely combined.
Step 10: Cream Butter
4.) In a mixing bowl, cream the butter with an electric mixer(stand mixer or hand-held) until light in color.
Step 11: Beat in Sugar
5.) Beat in sugar until a crumbly mixture as pictured.
Step 12: Beat in Eggs
6.) Beat in eggs one at a time to prevent any curdling.
Step 13: Beat in Vanilla
7.) Beat in vanilla extract(and vanilla seeds, if using). Scrape the bowl, and beat again.
Step 14: Pour in 1/3 Flour Mixture
8.) Pour in one-third of the flour mixture and beat until just combined.
Step 15: Beat in 1/2 of Heavy Cream
9.) Beat in half of the heavy cream until just combined.
Step 16: Finish Batter
10.) Continue alternating the flour mixture and heavy cream, beating after each addition and only beating until just combined. Overbeating will result in additional air bubbles in the batter and a very dense cake.
Step 17: Divide the Batter
11.) Divide the batter among a 12 cup muffin tin and bake for 15 to 20 minutes or until a toothpick, inserted into the middle of the cupcake, comes out clean.
While your cupcakes are baking, let's talk about the chemistry behind what causes the cupcakes to rise in the oven. Baking soda or sodium bicarbonate (NaHCO3), as well as baking powder, are active ingredients added to baked goods, such as the cupcakes we are baking, to make them rise. Recipes that use baking soda, and baking powder, as a leavening agent also contain an acidic ingredient such as lemon juice, milk, honey or brown sugar, in our case, it is the heavy cream, which serves as a reactive agent. The baking soda reacts with the acidic ingredient to produce tiny bubbles of CO2 that get trapped in the batter. The gas bubbles expand in the heat of the oven and rise up, giving you a fluffy and airy cake.
Step 18: Cream Butter for Frosting
12.) Allow the cupcakes to cool completely. While they cool, finish the frosting.
Ingredients To Finish Frosting:
1 Tbls. cocoa extract (for a vanilla German buttercream, use vanilla extract)
1 Cup butter, at room temperature
Steps To Finish Frosting:
1.) Allow the custard you previously made to come to room temperature.
2.) Cream butter until light in color, and fluffy.
Step 19: Gradually Beat in Custard
3.) Gradually beat in the custard you made, beating after each addition.
Step 20: Beat in Cocoa Extract
4.) Scrape the bowl and then beat in the cocoa extract.
Step 21: Fill and Frost Your Cupcakes
5.) Fill and frost your cupcakes however you would like. As you see, I went for the classic soft-serve ice cream sort of look on top, but you can frost them however you would please.