I've got a banana bread recipe whose main ingredients are as follows (for
one loaf).

1-1/3 cups flour
3/4 tsp salt
1/2 tsp baking soda
1/4 tsp baking powder
5 TBS butter
2/3 cup sugar
2 eggs
1 cup mashed banana
1/2 cup nuts

This is way too sweet for me and my audience. If the sugar were eliminated
completely, what would be the best way to adjust for that?