I like to use all the leftover heels of bread that we end up with at the end of any given week. But one big loaf works too!
For the bread pudding:
For the topping:
Prep. Preheat the oven to 350°F. Prepare a 9 x 13″ casserole dish with butter: cut 1/2 stick of butter into 3 or 4 pieces and microwave for 20-30 seconds until melted. Use a pastry brush or paper towel to add a thick layer of butter to the bottom and all sides of the pan.
Make the banana mixture. In a large mixing bowl, combine 3/4 cup brown sugar and 3 bananas. Mash the bananas with a fork until pretty smooth. Add 1/4 cup ground flax seed, 1/4 cup chia seeds, remaining melted butter plus 3 teaspoons pumpkin pie spice (or individual spices) and 1/2 teaspoon salt. Stir.
Add the milk mixture. To the banana bowl, add 3 cups milk, 2 eggs, 2 egg yolks and 1 teaspoon vanilla. Stir until the eggs are totally incorporated.
Cut the bread into pieces. Rip the bread or use a bread knife to make 2-ish inch pieces. Line the buttered casserole dish with bread.
Bring on the bananas. Slice the fourth banana into small pieces and tuck in between pieces of bread, scattering these larger bites of banana throughout the pan. Pour the banana and milk mixture over the top. Gently press down on the bread until the liquid is absorbed, about 5 minutes.
Bake. Place the casserole dish on a parchment covered baking sheet (for easy cleanup in case of overflow) and bake until the liquid is completely cooked and the bread looks fluffy. This takes about 1 hour.
Serve. Open a can of sweetened condensed milk and drizzle on top.