Gooey Chocolate Buttermilk Sheet Cake

Ingredients: 2 cups (280g) all purpose flour,2 teaspoons baking soda,1 tablespoon butter,1/2 cup (125ml) buttermilk,3 tablespoons cocoa powder,2 large eggs, beaten,1 pound (500g) icing sugar,1 cup milk,1 teaspoon salt,1 1/2 cups sugar,1 teaspoon vanilla extract,1/2 cup (125ml) vegetable oil,1 cup water
Instructions:

1. Cake:Preheat oven to 350 F (180C).In a large saucepan, bring to a boil the water, cocoa, oil and butter or margarine.
2. Mix the flour, sugar, salt and soda in a large mixing bowl.
3. Whisk in the hot mixture and mix well.To this add the buttermilk, vanilla and the beaten eggs; continue mixing.
4. Pour the batter into a greased and floured 9″x13″ oblong baking pan.
5. Bake in the preheated oven for approximately 20 minutes or until a toothpick comes out clean when inserted in the middle.
6. Remove from the oven and frost while still warm.Frosting:In a large pan set over medium heat, melt the butter and the cocoa powder and milk.Stir in the sugar and vanilla; whisk until smooth.
7. Add the chopped nuts if desired; stir well and spread on the warm cake.
8. Let cake cool before serving.

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