Copycat Magleby's Chocolate Cake

makes a TON ...1 8x8 and 1 9x13  fine to use 2 9x13 pans...just wouldn't be as thick

2 c. unsalted butter
2 c. water
3/4 c. cocoa plus 2 heaping Tbsp
4 c. flour
2 c. sugar
1 1/2 tsp salt
4 eggs lightly beaten
2 tsp baking soda
1 tsp baking powder
2 c. brown sugar
2 tsp vanilla
1 c. sour cream

Preheat oven to 325.  In small saucepan, heat butter until melted and add water and cocoa powder and whisk until smooth.  Bring to a boil and let boil for 30 sec.  Set pan aside and let cool.  
In separate bowl sift together flour, sugar and salt.  Add cooled chocolate mixture and stir until just combined and smooth.
In small bowl, add eggs, baking soda, baking powder, and whisk until smooth.  Mixture will start to foam but that is normal.  Stir in the brown sugar and vanilla and whisk until smooth.  Pour the egg mixture into the batter and gently stir until all combined.  
Fold in the sour cream gently.  
Divide into 3 greased (or parchment lined) 9 inch cake pans (or 1 8x8 and 1 9x13 or 2 9x13).  Bake at 325 for 30-35 min (or longer depending on the pans you use) Let cool.  Put cakes into freezer before frosting to make it easier.  

6 c. powdered sugar
1/2 c. room temperature butter
1/2 c. cocoa
Mix together with a rubber spatula until no big chunks of butter are left.  (will be very powdery still)
1/2 c. half and half (or milk, or cream and milk mixture) 
1 tsp vanilla
Stir with the rubber spatula