Chocolate Whirlaway cake: A classic marbled cake recipe from 1950

Instructions

1. Mix 1 square unsweetened chocolate, 2 tablespoons hot water, and 1/4 teaspoon soda, and 1 tablespoon sugar in small bowl -- let stand while mixing cake.
2. Stir shortening just to soften, then sift in flour, baking powder, soda, salt and sugar sifted together.
3. Add milk and vanilla and mix until flour is dampened, then beat 300 strokes by hand or two minutes on mixer at low speed.
4. Add eggs and beat 150 strokes by hand or one minute on the mixer at low speed.
5. Melt chocolate in the hot water with the fourth teaspoon of soda and tablespoon of sugar and let stand while mixing cake.
6. Add chocolate to one-fourth of batter, mixing only enough to blend.
7. Put large spoonsful of batter into pans lined with greased waxed paper, alternating the plain with the chocolate.
8. With a knife cut carefully through the batter in a wide, zigzag course.
9. Bake in moderate oven (350 degrees) 35 minutes or until done.
10. Cool in pans on cake rack for five minutes.
11. Then loosen from sides with spatula, turn out, and remove paper and turn right side up on racks to cool.
12. Use any favorite chocolate frosting.