Think of these when you have a couple of bananas that are over-ripe and you want chocolate, not banana bread. This recipe makes a dense, moist, rich brownie. Make 24 hours in advance so flavors can mellow, if possible. (That's if you can keep them from disappearing.) Many of us don't have macadamia nuts on hand so walnuts would work as well. If you don't normally frost your brownies leave out the chips and bake as usual. Adding the nuts to the batter is good, also, but put the batter in a bowl and fold nuts in. If you try adding them to the bater in the processor,the nuts will be ground too fine and disappear.