Orange Cake

Beat the butter and sugar until creamy

Add the egg yolks one at a time, beating well after each addition

Combine the flour, yeast, and baking powder

Alternate adding the butter mixture and buttermilk to the dry ingredients

Add the grated orange zest and chopped walnuts

Beat the egg whites until stiff peaks form

Fold the egg whites into the batter

Pour into a greased tube pan or Bundt pan

Bake in a moderate oven until a toothpick inserted comes out clean

Remove from the oven, mix in 1/2 cup of sugar and orange juice

Drizzle over the warm cake still in the pan

Let cool completely

Wrap tightly in plastic wrap and refrigerate for at least 3 hours

Thaw overnight in the refrigerator, then rewrap in foil or plastic wrap and freeze