Follow the box instructions. Line a 9×13-inch baking pan with parchment, then mix the batter from 2 boxes of Ghirardelli ...
Finally, I cooled each batch of brownies in the pan for 20 minutes and then transferred them to a rack to rest for another 20 ...
I have been a devotee of Ghirardelli Double Chocolate Brownie Mix. I love them so much that I buy the mix in bulk from Costco ...