In a medium bowl, combine the eggs and milk together using a whisk.
Pour in the vanilla, cinnamon, and sugar. Whisk again to combine.
Pour the egg-milk mixture atop the cubed brioche bread, making sure all the bread is soaked with the liquid. Use a spatula to mix if necessary.
Using a large cookie scoop or spoon. scoop some of the french toast batter/bread cubes into a muffin tin. Top with a little coarse sugar and bake at 350º for 25 minutes.
Once cooled, drizzle the maple glaze on top.
For the Glaze
Whisk together the powdered sugar, milk, and maple syrup until the powdered sugar is completely dissolved.
Notes
Be sure to soak the bread well so that it absorbs all the liquid.When baking, the top should be crisp, and then inside should be creamy, not soggy. Time the muffins at the time listed in the recipe card, but also be sure to check your oven temp with a thermometer too!Whisk the eggs and milk REALLY well to whip air into the mixture so that when the brioche soaks, it will also aid in the rise and overall texture.