3 cups (18 ounces) milk or semi sweet chocolate chips
11/2 cups sour cream or non dairy substitute, at room temperature
2 cups flour
1 1/2 cups sugar
1 cup water
1 1/2 sticks (3/4 cup) butter or margarine (not spread), at room temperature
3/4 cup unsweetened cocoa powder
3 large eggs
1 1/2 teaspoons vanilla extract
1 teaspoon baking soda
1/2 teaspoon baking powder
1/2 teaspoon salt
Make the Frosting: Melt chocolate chips according to package directions. Immediately whisk in sour cream. Scrape into a metal bowl. Refrigerate, stirring a few times, until thick enough to spread (may take up to 4 hours). Makes 31/4 cups.
Preheat oven to 350.. Grease and flour two 9-inch round cake pans. In a large bowl with electric mixer on low speed, combine all the cake ingredients and beat ingredients just until blended. Increase mixer speed to high and beat 3 minutes, scraping down sides of bowl a few times. Divide batter between prepared pans. Spread evenly. Bake 25 to 30 minutes until a pick inserted in center of cakes comes out clean. Cool in pan on rack 10 minutes. Turn out on rack, invert and cool completely.
To frost: Place 1 cake layer on serving plate. Spread with 1 cup frosting. Top with second cake layer. Frost sides and top with remaining frosting.
The cake layers can be wrapped well and refrigerated up to 3 days or frozen up to 3 months. Make the frosting about 4 hours before you plan to ice the cake, so it has time to chill to spreading consistency.