All-In-One-Pan Chocolate Cake

Directions

Heat oven to 350℉ (180℃).

Sift flour, sugar, cocoa, baking soda and salt into a 9×13-inch baking pan.

Add water, oil, vinegar and vanilla.

Mix with a large rubber spatula until smooth, taking care to mix ingredients along edges.

Bake until toothpick inserted in center comes out clean, about 40 minutes.

Cool completely on wire rack.

FROSTING: combine butter and shortening in a food processor or mixing bowl. Add sugar and vanilla.

Mix until smooth, about 2 minutes. Slowly drizzle in milk.

Beat 2 minutes in food processor or 7 to 10 minutes with a mixer, until smooth, satiny and fluffy.

Chill just 20 minutes before frosting.