Grease a 9x12-inch cake pan with shortening.

Preheat oven to 350°F.

Measure ingredients directly into the baking pan:

3 c. cake flour
2 tsp. baking soda
1 tsp. salt
2 c. sugar
1/2 c. cocoa

Make three holes in dry ingredients and place:

2 tablespoons vinegar
2 tsp. vanilla
2/3 cup oil

Pour 2 cups water or milk over all, stir with fork, making sure to get all the corners mixed, too.

Bake at 350°F for 40 minutes or until cake tests done.