Ingredients
Cake
1/2 pound (2 sticks) unsalted butter, diced, at room temperature, plus more for the pans
3 cups all-purpose flour
1/4 teaspoon kosher salt
1 heaping teaspoon baking powder
12 ounces 67% bittersweet chocolate, preferably Olive and Sinclair, chopped
2 cups sugar
5 large eggs
1 cup evaporated milk
1/2 cup water
2 teaspoons pure vanilla extract
Icing
2 cups sugar
1 cup evaporated milk
5 ounces unsweetened chocolate, chopped
8 tablespoons (1 stick) unsalted butter, cut into chunks
1 teaspoon pure vanilla extract
Preparation
Cake: 1. Position rack in the middle of the oven and preheat to 350°F. Lightly butter as many 9-inch round cake pans as you have-you want to create a total of 10 layers, baking 2 or 3 layers at a time. If you only have two or three pans, cool them between batches and butter them again as needed.
Sift the flour, salt, & baking powder into a small bowl; stir to combine well. Set aside.
Put chocolate in the top of a double boiler over low heat; the water should never be hotter than a simmer. Stir the chocolate with a silicone spatula until it melts, scraping down the sides as necessary. Remove from heat.
In a large mixing bowl beat the butter & sugar on medium speed until light and creamy, about 5 minutes. Add eggs one at a time, beating until smooth after each addition. Reduce speed to low; add the sifted dry ingredients 1 cup at a time, beating until incorporated. Add evaporated milk & melted chocolate; beat just to combine. Add water & vanilla, beating until well combined.
Place scant 2/3 cup batter in each prepared cake pan; use the back of a spoon or an offset spatula to spread the batter evenly. Bake 2 or 3 layers at a time for 8 to 9 minutes-a layer is done when you hold it near your ear and do not hear it sizzle. Allow the layers to cool in the pans for 10 minutes. Turn them out onto baking racks, using a metal spatula to ease them out of the pans, and let cool completely.
Icing: Combine sugar & evaporated milk in medium saucepan over medium-low heat. Add chocolate & butter and heat, stirring, until they’ve melted. Increase the heat to medium and cook, stirring occasionally, for 10 minutes, until the mixture has emulsified and is smooth. stirring to combine. Icing will be thin, but it will thicken as it cools.
Assemble: 1. Place 1 layer on a cake plate & spread 2 or 3 spoonfuls of icing on top. Repeat with remaining layers. Then cover top & sides. Let cake stand for 1 hour before serving.
