Coat 9x13 glass baking dish with cooking spray

Cut your bread into bite sized pieces & place in pan covering the bottom

Layer in about 1 cup of the marshmallows & 1 cup of the caramel portioning out as evenly across the top of the bread as possible

Add another layer of bread followed by the remaining marshmallows & caramel

In a small bowl - whisk together milk, eggs & vanilla extract

Pour evenly over your layers

Cover & refrigerate at least 2 hours but as long as overnight

When ready - preheat oven to 350 degrees

In a small bowl, combine flour, brown sugar & butter cubes

Work together with your fingers or a pastry cutter until you reach a coarse crumbs consistency

Sprinkle evenly over the top of the prepared dish & bake for 35-45 minutes or until golden brown

Serve immediately - preferably with a little homemade caramel drizzle on top