Every time I bake banana bread, I end up with the middle of the top of
the loaf undercooked.

I love it very moist and dense and won't eat it at all if it gets
overcooked, but I can't figure out how to leave it in long enough to
get the top cooked while not overcooking the middle and sides.

I have a convection oven and have tried both convection and regular
baking options without success in either.

I use a high quality nonstick loaf pan.

TIA.

Robert