Stir breadcrumbs, sugars, pecans, spices, 4 tablespoons butter, and bitters to make a crumb.
Wipe 1 tablespoon of melted butter inside a pie plate.
Slice 3 bananas and arrange them in a single layer in the pie plate.
Sprinkle half of the crumb over the bananas.
Repeat, making another layer of bananas and another layer of crumb.
Bake for 40 minutes, until slightly browned.