Heat the oven to 350°F. Grease and flour 2 (8-inch) round cake pans.
Stir the flour, cocoa, baking soda and salt in a medium bowl.
Beat the butter and sugar in a large bowl with an electric mixer on medium speed until the mixture is light and fluffy. Beat in the eggs, one at a time, beating well after each addition. Beat in the vanilla extract.
Reduce the speed to low. Add the flour mixture alternately with the tomato juice, beating well after each addition. Pour the batter into the cake pans.
Bake for 35 minutes or until a toothpick inserted in the center comes out clean. Cool the cakes in the pans on wire racks for 10 minutes. Remove the cakes from the pans and cool completely on the wire racks. Frost and fill with the Creamy Butter Frosting. Refrigerate until ready to serve.
Place 3/4 cup (1 1/2 sticks) butter, softened, 1 package (16 ounces) confectioners' sugar, 1/4 cup milk, 1/2 teaspoon vanilla extract and 1/4 teaspoon salt in a medium bowl.
Beat with an electric mixer on low speed until the mixture is smooth. Increase the speed to medium, adding more milk, if needed, until desired consistency.
Makes 2 1/2 cups.