Liberally oil a baking sheet (two if you have them); set aside. Preheat the oven to 350°F.
Whisk together the eggs, milk, and vanilla extract. Add about 1/2 teaspoon of ground cinnamon and whisk some more. Place one slice of bread at a time in the batter, turning over several times until the bread is good and wet. (Take note on how wet the bread is so that you can adjust the recipe to your liking for the next time you make this French toast.)Sprinkle each side with additional cinnamon and baste the cinnamon with more of the egg-milk mixture. Allow any excess to drip back into the bowl. Transfer the soaked bread to the baking sheet. Repeat until you run out of bread or batter.
Serve immediately or allow to cool to room temperature and freeze in a single layer and store in a zipper storage bag.
*Egg-Free:
Substitute each egg with 1 tablespoon fat of choice such as melted butter, coconut oil, etc. plus 2 tablespoons liquid from a can of mild-flavored white beans like cannellini/white kidney or navy.
For Egg-Free Bread:
Try using the above-linked recipe for Gluten Free Egg Free Bread.
https://glutenfreerecipebox.com/baked-gluten-free-french-toast-in-a-sheet-pan/