Step 1

Heat oven to 375 degrees F.

Step 2

Spray 9x13 pan with baking spray. Set aside.

Step 3

Melt butter in a sauce pan.

Step 4

Whisk in cocoa powder. Set aside.

Step 5

Beat eggs, sugar, and vanilla at high speed of an electric mixer for 10 minutes.

Step 6

Turn mixer to low and stir in chocolate mixture.

Step 7

Add flour and mix until blended.

Step 8

Stir in nuts.

Step 9

Pour into prepared pan and bake for 35 minutes.