Preheat your oven to 350°F (175°C) and grease a 12-cup muffin tin.
In a large bowl, whisk together the eggs, milk, sugar, vanilla, cinnamon, and salt.
Add the cubed bread into the egg mixture. Stir until every piece is coated and soaking in the goodness.
Let it sit for about 5 minutes so the bread can soak up all that flavor.
Divide the mixture evenly into the muffin cups.
Drizzle melted butter over the tops and sprinkle generously with cinnamon sugar.
Bake for 20–25 minutes or until the tops are golden and slightly crispy.
Cool for a few minutes before removing. Eat warm, preferably with coffee or a smile.