These are fabulous bars...really fantastic! I used a whole egg, and I added 1 t. baking powder to the base mixture. Also, to simplify things, when the base layer came out of the oven, I sprinkled the 2 c. of chocolate chips over it while it was hot, waited about 3 minutes, and then spread them evenly with a butter knife once they'd melted. Then sprinkled with chopped toasted almonds. At first I thought the almond extract in the mix didn't taste quite right, but once the bars cooled the taste was excellent! Everyone who sampled these thought they ROCKED. I kept them in the fridge. Would most certainly make these again!!