Chocolate Texas Sheet Cake

From: Sue
Ingredients:

• 2 cups all-purpose flour
• 2 cups granulated sugar
• 1/2 cup sour milk (2 Tablespoons vinegar + enough milk to make 1/2 cup)
• 1 teaspoon baking soda
• 1 cup + 1/2 cup margarine
• 1 cup + 6 Tablespoons water
• 4 Tablespoons + 4 Tablespoons cocoa
• 2 eggs
• 1 teaspoon + 2 Tablespoons vanilla
• 1 pound (ish) powdered sugar

Directions:

1. Preheat oven to 400 degrees. Grease and flour cookie sheet.
2. Sift together flour and sugar.
3. In a separate bowl, mix sour milk and baking soda.
4. Bring 1 cup margarine, 1 cup water and 4 Tablespoons cocoa to boil and then pour over flour mixture.
5. Add eggs, sour milk mixture and 1 teaspoon vanilla and mix well.  Pour onto cookie sheet and bake for 20 minutes.
6. Meanwhile, whisk together 1/2 cup margarine, 6 Tablespoons water and 4 Tablespoons cocoa and bring to a boil. Remove from heat and add 2 Tablespoons vanilla and powdered sugar (add in parts, until mixture reaches desired consistency). Mix well. Frost cake while warm.