1 cup mashed potatoes (from one large Idaho® baked or steamed russet potato)
1 cup (3 ½ ounces) grated chocolate
1 cup (4 ounces) finely chopped nuts
2 cups all-purpose flour
2 teaspoons baking powder
1 teaspoon ground cloves
1 teaspoon ground nutmeg
1 teaspoon ground cinnamon
Instructions:
Preheat the oven to 350°F. Line a 9x13 cake pan with parchment paper and lightly grease the pan.
Mix the flour, baking powder, and spices in a bowl.
Place butter and sugar in a stand mixer and beat until light and fluffy. Add the egg yolks one at a time, beating well after each addition. Add the milk and potatoes.
Add the dry ingredients and mix just until combined.
In a clean bowl, beat the egg whites until stiff but not dry. Fold one-third of the egg whites into the batter, then gently fold in the remaining whites. Pour the batter into the prepared pan and bake for 35-40 minutes, or until a tester comes out clean.