Preheat oven to 350°F and lightly spray your muffin pan with oil or nonstick spray. Set pan aside.
Cut bread into 1" cubes, then set aside.
6 cups cubed bread
To a large bowl, add eggs, milk, Greek yogurt, and vanilla. Whisk until everything is evenly combined.
5 large eggs, 1 cup milk, 1/2 cup Greek yogurt, 2 tablespoons pure maple syrup, 1 teaspoon vanilla extract
Add bread and cinnamon to the egg mixture. Use a spatula to gently toss, until all bread pieces are evenly coated and soaked in the egg mixture.
1 teaspoon ground cinnamon
Evenly divide the bread mixture into the greased muffin tins. Place in the oven and bake for 15-18 minutes, or until tops are slightly browned and there is no jiggle anywhere in the muffin when you jostle the pan.
Let muffins cool for 2-3 minutes in the pan, then transfer to a wire rack to finish cooling, if not enjoying immediately. Store leftover or meal prepped French toast muffins in an airtight container in the fridge.
Notes
Please note that nutrition information may vary greatly depending on specific ingredients you use.