Preparing french toast in large volume takes organization, and you may need to borrow some extra kitchen space to pull it off. The best way is to prepare the toast in the oven, which allows for larger batches. You will need extra refrigeration and oven space to manage it. Many community halls and larger churches have commercial-quality kitchens, and are happy to rent them out for this sort of use. A local restaurant or bakery may also be willing to help out, if asked.
Start the day before. In a very large pot or mixing bowl, whisk together the eggs, milk, sugar, salt, vanilla and cinnamon until the eggs are fully incorporated into the milk and the sugar has dissolved. Make multiple smaller batches if necessary, rather than one large batch. If you have access to a commercial kitchen, you can do this quickly in a large bakery-style mixer.
Lay out as many foil pans as your work space permits, and spray them with the pan spray. Line the bottom of each pan with bread, cutting some slices into strips to fill the empty places in the pan.
Pour five cups of the egg and milk mixture over the bread in each pan, taking care to cover the bread completely. Some brands of bread will absorb more liquid than others, so you may need to add a little extra.
Cover the pans with aluminum foil and refrigerate. Repeat until all the pans are filled. Allow the pans to rest overnight in the refrigerator so the bread can absorb all of the custard.
Heat your oven or ovens the next day, to 425 degrees Fahrenheit. Remove the foil covering, and place two pans on each of the oven's racks, or three if you have a commercial-sized oven. Bake for approximately 30 to 35 minutes, rotating the pans from one shelf to the other at the mid point. The French toast should be pale golden on top, and the egg mixture should be set in the middle.
Remove the pans from the oven. Cover them again with aluminum foil, and stack them on top of the stove to keep warm while the next batch cooks. When you are ready to begin serving, cut each pan of French toast in half lengthwise, and then into six slices across. This yields six portions per pan, at two generous slices per portion.
- University of Mississippi: Baked French Toast Recipe
- "Professional Cooking, 5th Ed."; Wayne Gisslen; 2003
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