Texas Sheet Cake

*This is not the best picture but it really is yummy. I made it for a bar-b-que and it was a hit.

1 cup butter or margerine
1 cup water
1/4 cup cocoa
2 cups all purpose flour
2 cups sugar
1 tsp. baking soda
1/2 tsp. salt
1/2 cup sour cream

Icing:
1/2 cup butter or margerine
1/4 cup plus 2 Tbs milk
3 Tbsp. baking cocoa
3 3/4 cups powder sugar
1 tsp. vanilla extract

Cake:
Bring butter, water and cocoa to a boil and remove from heat. combine flour, sugar, baking soda and salt and add to cocoa mixture. Stir in the sour cream until smooth. Pour into 15 by 10 inch baking pan. Bake @350 for 20-25 minutes.

Icing:
In a sauce pan melt butter; add milk and cocoa. Bring to a boil. Remove from heat. Whisk in sugar and vanilla until smooth. Pour over warm cake.
I think this recipe is from Taste of Homes magazine.