1. Step 1- Preheat oven to 350 degrees. Line a 9x13 pan with parchment paper. Set aside. 2. Step 2- In a bowl combine melted butter and cocoa powder. Mix on medium speed. 3. Step 3- Add the eggs and beat until thickened and smooth. 4. Step 4- Now add the sugar and mix until well combined, then add the flour and mix another 2 minutes. 5. Step 5- Spread the mixture into the pan and bake for 20 minutes until center is set. Top the brownies mixture with mixed nuts. Allow brownies to cool down before serve.