Sweet Potato Cake
In my next venture with this cake, because there will seriously be a next time, I will use 4 egg whites, 1 cup sugar, a pinch more cream of tartar and a whole teaspoon of vanilla. Why? I could not stop stealing a bit here and there of the frosting, the kids couldnt stop. There just needs to be more of it! Hubba, hubba, hubba!
1 1/2 cups cooked and mashed sweet potatoes
2 cups (250 grams) all-purpose flour
1 3/4 teaspoons baking powder
1/2 teaspoon baking soda
1/2 teaspoon table salt
1 teaspoon ground cinnamon
1/2 teaspoon ground ginger
1/4 teaspoon ground cloves
1/2 cup (1 stick or 115 grams) unsalted butter, at room temperature
1 cup (190 grams) packed light brown sugar
1 teaspoon vanilla extract
2 large eggs
3 large egg whites
3/4 cup granulated sugar
Pinch of salt
1/4 teaspoon cream of tartar (will help stabilize egg whites, don’t worry if you don’t have it)
1/2 teaspoon vanilla extract
Heat oven to 350 degrees F. Line the bottom of an 8- to 9-inch square pan with parchment paper, then butter the paper and sides of the pan. Or you could use nonstick spray.
Whisk flour, baking powder, baking soda, salt and spices together in a medium bowl. In a large bowl, beat butter and brown sugar together with an electric mixer until light and fluffy, about 2 to 3 minutes. Add vanilla and eggs, and beat until just combined. Mix in sweet potato puree, then stir in dry ingredients just until they disappear.
Spread batter in prepared pan, and bake cake until a toothpick inserted into the center comes out clean, about 35 to 40 minutes. Let cake rest in pan for 5 minutes on a cooling rack, then invert onto cooling rack, and let cool completely.
Make frosting:Place egg whites, granulated sugar, a pinch of salt and cream of tartar in a heatproof bowl set over a saucepan of gently simmering water. Whisk mixture for 3 minutes, until whites are warmed. Remove bowl from top of saucepan, then, with an electric mixer, beat egg white mixture on high speed until stiff, glossy peaks form, about 4 to 7 minutes longer. Add vanilla and mix until combined.