Preheat oven to 425 degrees. Butter a 13x9 inch baking pan and set aside.

In a small sauce pan, melt butter over medium heat. Once butter has melted, stir in brown sugar until dissolved and mixture is smooth. Pour mixture into the bottom of a 9x13 pan and spread evenly.

Add bread cubes to the pan, spreading over the top of the brown sugar/butter mixture.

In a medium sized bowl, whisk together the eggs, milk, vanilla, and 1 tsp of cinnamon. Pour egg mixture over the top of bread cubes, ensuring that all pieces of bread are saturated. Sprinkle with remaining 1 teaspoon of cinnamon and 1 tablespoon of brown sugar.

Bake in preheated oven for 25-30 minutes until top is golden brown. Remove from oven and sprinkle with powdered sugar if desired. Enjoy!