BEST Chocolate sheet cake

Once again Pioneer Woman is the GREATEST!!! I LOVE LOVE LOVE chocolate cake!! We signed up to have the missionaries over Saturday for dinner so I decided to make a nice big meal and make a new dessert. I found this best chocolate sheet cake recipe on Pioneer Woman and decided this was the one. You HAVE to try this if you're a chocolate fan! Warm, fudgy, gooey, maybe I shouldn't have discovered this recipe because this is by far my favorite sheet cake ever!

Combine in mixing bowl:
2 c flour
2 c sugar
1/4 t salt

In a saucepan melt:
2 sticks butter
Add 4 heaping Tb cocoa. Stir together.
Add 1 c boiling water, allow mixture to boil for 30 secs, then turn off heat. Pour over flour mixture, and stir to cool slightly.

In measuring cup, pour 1/2 c buttermilk.
Add:
2 beaten eggs
1 t baking soda
1 t vanilla
Stir buttermilk mixture into butter/chocolate mixture. Pour into sheet cake pan and bake at 350 for 20 mins.

While cake is baking, make icing:
Chop 1/2 c pecans (if desired)
Melt 1 3/4 sticks butter in saucepan
Add 4 heaping Tb cocoa, stir to combine, then turn off heat.
Add:
6 Tb milk
1 t vanilla
1 lb minus 1/2 c powdered sugar
Stir together.
Add pecans, and pour over warm cake.

Cut into squares, eat, and totally wig out over the fact that you've just made the best chocolate sheet cake ever!!