Rich Chocolate Cake
From Becky Sanchez

Makes 8 cups batter
1 1/2 cups (3 sticks) unsalted butter, room temperature, plus more for pans
3/4 cup Dutch-process cocoa powder, sifted, plus more for pans
3/4 cup boiling water
1 cup whole milk
2 1/4 cups granulated sugar
2 teaspoons pure vanilla extract
4 large eggs, room temperature
3 cups sifted cake flour (not self-rising)
1 teaspoon baking soda
1 1/2 teaspoons coarse salt

Preheat oven to 350 degrees. Butter pans. Line with parchment cut to fit. Butter parchment. Dust with cocoa. Tap out excess.
Stir together cocoa and boiling water. Add milk, and whisk until smooth.
Beat butter with a mixer on medium speed until light and fluffy. Add sugar in a slow stream, and beat well, about 3 minutes. Beat in vanilla. Add eggs, one at a time, beating well after each addition.
Sift together flour, baking soda, and salt. Reduce mixer speed to low. Add the flour mixture in 3 additions, alternating with the cocoa mixture.
Pour batter into pans, and bake until a few crumbs remain on testers (batter amounts and cooking times follow). Let cool in pans on wire racks for 45 minutes. Unmold, and remove parchment. Let cool completely on wire racks. Batter Amounts and Cooking Times for 2-Inch-Deep Pans 5-inch: 1 1/4 cups batter, 45 minutes 7-inch: 2 1/4 cups batter, 45 minutes 9-inch: 4 cups batter, 50 minutes 11-inch: 6 cups batter, 50 minutes

Chocolate Buttercream Frosting
(I did half this recipe with semi-sweet chocolate and half with white chocolate to make 2 different frostings.)
Makes enough for 15 cupcakes (about 3 cups)
2 cups sugar
1 cup egg whites (about 6 large)
1 1/4 cups (2 1/2 sticks) unsalted butter, cut into small pieces
16 ounces dark chocolate, melted and cooled slightly

Place sugar and egg whites in the bowl of an electric mixer set over (but not touching) a pan of simmering water. Whisk constantly until mixture is heated and sugar is dissolved. Attach bowl to an electric mixer fitted with the whisk attachment and continue whisking until cooled and stiff peaks form, about 7 minutes.
With the mixer running, add butter, one piece at a time, until completely incorporated. Continue whisking until a light, fluffy cream has formed. Stir in chocolate until well combined.

Chocolate Ganache Filling
Makes 1/2 cup
6 Tablespoons heavy cream
1/2 teaspoons light corn syrup
1.5 ounces semi-sweet chocolate, finely chopped

Bring cream and corn syrup to a simmer in a small saucepan. Place chocolate in a food processor. With the machine running, add the cream mixture in a slow stream. Process until smooth and shiny.
Refrigerate in an airtight container, stirring occasionally, until thick enough to spread. Use immediately, or refrigerate in an airtight container for up to 3 days.