• 10 eggs, at room temperature

    1 teaspoon vanilla extract

    6 cups (750 g) all-purpose flour

    1 1/2 teaspoons salt

    2 tablespoons baking powder

    2 1/2 cups (600 ml) nonfat buttermilk

    3 or 4 drops red food coloring

    Ingredients for the buttercream

    10 egg whites

    2 cups (400 g) granulated sugar

    Pinch salt

    1 1/2 pounds (685 g) unsalted butter

    Method for the cake

    Preheat the oven to 350°F (175°C). Line a half sheet pan with parchment and spray with nonstick cooking spray. Spray a large tube or angel food baking mold with nonstick baking spray. Set aside.

    In the bowl of a stand mixer fitted with the whisk attachment, cream the butter and granulated sugar until light and fluffy, 5 to 10 minutes. Scrape the sides and bottom of the bowl a few times. Add the eggs, one at a time, beating for 30 seconds between each addition. Add the vanilla.

    In a large bowl, stir together the flour, salt, and baking powder. With the mixer on low, alternate additions of the flour mixture and the buttermilk. Using a large rubber spatula, scrape the bottom and sides of the bowl to ensure the batter is well mixed.

    Transfer a little less than half of the batter to a large mixing bowl. Add the food coloring to the bowl and stir to distribute the color.

    Spread the red batter in an even layer in the prepared half sheet pan and bake until the cake is just barely done and feels firm when touched but doesn't spring back, 10 to 15 minutes. Allow to cool completely.

    Put half of the un-dyed batter in the bottom of the tube pan. Using a 3-inch (7.5 cm) heart-shaped cookie cutter, stamp out 14 or 15 heart shapes from the red cake. Place the hearts in the tube pan, rounded side down into the batter and point sticking up. Don't press the hearts all the way down into the batter, just enough that the batter keeps them upright. Place them as close together as you can while still keeping the hearts properly angled in the round.

    Fill a large pastry bag with the remaining un-dyed batter and pipe it into the tube pan, making sure to fill any hard- to-reach areas and covering the hearts completely. Bake for 45 to 50 minutes or until the cake is golden brown and springs back when gently touched. Allow to cool completely in the pan.

    Method for the buttercream

    In the bowl of a stand mixer, combine the egg whites, granulated sugar, and salt. Constantly whisk the egg white mixture over a bain marie (a large saucepan half full of simmering water) until the sugar has completely dissolved and feels warm to the touch (attach a thermometer and make sure the mixture reaches 160°F / 72°C if you are nervous about uncooked eggs.

    Transfer the bowl to a stand mixer fitted with the whisk attachment and whisk on high until the mixture quadruples in volume and the bowl is cool to the touch.

    Add the butter, a few tablespoons at a time, until the buttercream thickens. The icing may look as if it's starting to separate and appear chunky; this is perfectly normal. Just walk away for a few minutes while the mixer does its work, and you'll come back to beautiful buttercream.

    Assembly

    Run a long, thin knife along the edge of the baking pan to release the cake. Place a cake platter on top of the tube pan, face down, and flip the pan over. Gently left the pan off so the cake remains on the platter.

    Coat the cake with a smooth layer of buttercream. Serve immediately, or store in the refrigerator for up to 3 days.

    KRAPFEN

    Makes 20 Krapfen

    Ingredients for the sponge

    3/4 cup (180 ml) warm whole milk

    2 teaspoons dry active yeast

    Pinch granulated sugar

    1 1/4 cups (175 g) bread flour

    Ingredients for the dough

    2 teaspoons dry active yeast

    1/4 cup (60 ml) warm whole milk

    3 egg yolks

    1 teaspoon vanilla extract

    Zest of lemon