Chocolate Sheet Cake

This is one of my favorites, from Pioneer woman

cake:
2 cups flour
2 c. sugar
1/4 tsp. salt
1/2 c. buttermilk
2 large eggs
1 tsp. vanilla
1 tsp. baking soda
1/2 lb. butter (2 sticks)
4 heaping Tb. cocoa powder

icing:
1 3/4 stick butter
4 heaping Tb. cocoa powder
6 Tb. milk
1 tsp. vanilla
1 lb. powdered sugar
1/2 c. finely chopped pecans

1. preheat over to 350
2. In a large bowl, combine the flour, sugar, and salt; stir together, set aside
3. In another bowl, mix the buttermilk, eggs, vanilla, and baking soda; mix together, set aside
4. In a medium sauce pan, melt the butter and add the cocoa, whisk together
5. Once the butter is melted, add 1 c. boiling water; allow it to boil about a minute then turn off heat
6. Pour the chocolate mixture into the flour mixture. Stir together to cool the chocolate, then pour in the egg mixture
7. Stir together until smooth, poor into jelly roll pan
8. Bake for 20 minutes