This is a great one from my favorite cookbook (see below!). It has a wonderful (a little unique) flavor and a velvety texture.
Black and White Pound Cake
1/2 cup semisweet or bittersweet chocolate
1/3 cup hot water
3 T. cocoa
1 T. light corn syrup
4 cups cake flour
2 tsp. baking powder
1/2 tsp. salt
6 large eggs
1/2 cup milk
2 tsp. pure vanilla extract
1 1/2 cups (3 sticks) butter, softened
1/4 cup oil
3 1/2 cups powdered sugar
1/4 tsp. baking soda
1. Preheat oven to 325 degrees. Thoroughly grease a 10-inch angel food cake pan.
2. Combine chocolate, hot water, cocoa, and corn syrup in a saucepan. Heat over low heat until chocolate is just melted. Remove from heat.
3. In a large bowl, thoroughly whisk together the flour, baking powder, and salt
4. Whisk the eggs in a medium bowl. Blend in the milk and vanilla.
5. Beat the butter in an electric mixer until light and fluffy. Gradually add the oil. Slowly add the sugar. Beat until well-blended.
6. Add the dry ingredients alternately with the egg mixture to the butter mixture, beginning and ending with the flour. Beat until well-blended.
7. Remove a generous 2 cups of the batter. Add the baking soda to the chocolate mixture; then add the chocolate mixture to the reserved two cups of batter, gently folding together.
8. Using two large clean spoons, alternately place large spoonfuls of the chocolate and vanilla batters in the prepared pan, carefully spreading the flavors to they touch. Make a second layer of batter, this time placing spoonfuls of vanilla batter on the chocolate and the chocolate batter on the vanilla. Repeat, alternately the flavors, making 3-4 layers. Insert a kitchen knife into the batter starting about 1 inch from the funnel and circle the pan 2-3 times. Do not overwork. Firmly tap the pan two or three times on the counter to level batter.
9. Bake 1 hour and 20 minutes, or until a skewer inserted in the center comes out clean. Remove the cake from the oven; shake vigorously (this will loosen the sides and bottom). Let cool for 20-30 minutes. Invert before serving. Yield: 16-20 servings