To prepare enough buttercream to frost a two layer 9-in. round cake (or a three layer 8-in. round cake), you'll need one pound (450 g) unsalted butter, four large eggs, 1 cup (200 g) granulated sugar, 1/2 teaspoon (3 g) table salt, and 2 tsp. pure vanilla extract.
Start by cracking all four eggs into the metal bowl of a stand mixer. Add the sugar, salt, and vanilla extract to the bowl.
Whisk until the eggs, sugar, salt, and extract are evenly combined.
Find a pot that the mixing bowl can sit on without touching the bottom of the pan. Pour about 1/2-in. (about 1 cm) water into the pot and bring to a boil. Reduce heat to a simmer and place the mixing bowl over the water pot to form a double boiler. This will allow us to heat the eggs slowly, minimizing the chances that the egg proteins will tighten up (forming scrambled eggs). Whisk continuously over the steaming water until the eggs reach 160°F as measured by an instant read thermometer.
Once the mixture reaches 160°F, take it off the heat and beat on medium-high with the flat beater attachment for five minutes. The egg mixture will turn light yellow and fluffy. The mixture should have cooled by this time. Touch the side of the mixing bowl to check the temperature. If the mixture is too warm, it will melt the butter while you add it and the buttercream might not come together.
Reduce the mixer's speed to low and begin cutting pieces of butter into the mixer, waiting for ten to fifteen seconds before adding the next piece. One pound of butter should be cut into about 16 to 20 pieces (about 2 Tbs. per piece). During this process, the mixture will become lumpy, but don't worry about it, continue to cut pieces of butter into the mix until all the butter has been incorporated.
After all the butter has mixed in, continue to run the mixer until the mixture turns smooth and silky.}?>
The final buttercream should be easy to spread onto the cake and should taste distinctly of sweet butter without any lumps or grittiness.
|4 large (200 g) eggs||whisk||whisk over double boiler until 160°F||beat on medium-high speed 5 min.||beat butter in on low speed||beat until smooth and silky|
|1 cup (200 g) granulated sugar|
|2 tsp. (10 mL) vanilla extract|
|1/2 tsp. (3 g) table salt|
|1 lb. (450 g) unsalted butter||cut into 16 to 20 pieces|