Chocolate-Almond Marbled Poundcake

1/4 cup stick margarine softened
3 tablespoons vegetable shortening
1 1/3 cups sugar
3 large egg whites
1 cup low-fat buttermilk
1/2 teaspoon baking soda
2 1/2 cups sifted cake flour
1/4 teaspoon salt
3/4 teaspoon almond extract
1 ounce semisweet chocolate melted
cooking spray

Cream margarine and shortening; gradually add sugar, beating at high speed of a mixer until light and fluffy (about 5 minutes). Add egg whites, one at a time, beating after each addition. Preheat oven to 325ºF. Combine buttermilk and soda, and set aside. Combine flour and salt; beat at low speed Add flour mixture to creamed mixture alternately with buttermilk mixture, beginning and ending with flour mixture.

Reserve 2 cups of batter, pour remaining batter into a bowl. Stir almond extract into reserved batter; stir chocolate into remaining batter. Spoon almond batter alternately with chocolate batter into a 9 x 5-inch loaf pan coated with cooking spray. Swirl batters together using the tip of a knife. Bake at 325¼F for 1 hour and 10 minutes or until a wooden pick inserted in center comes out clean. Cool in pan 10 minutes on a wire rack. Remove from pan; cool completely.