Banana Cream Pie Bread Pudding

Name: Banana Cream Pie Bread Pudding
Ingredients: 1 loaf challah bread; 1 (3.4-oz.) package instant vanilla pudding; 3 1/2 c. milk, divided; 3/4 c. packed brown sugar, divided; 2 large eggs; 1 tsp. pure vanilla extract; Pinch kosher salt; 2 c. heavy cream; 4 bananas, sliced, divided; 1 1/2 c. Nilla wafers; 3 tbsp. butter; 2 c. whipped topping; 1/2 c. crushed Nilla wafers