Slice the bread into 1" slices, then each slice into thirds. Arrange half of the bread pieces in one layer in the pan. Sprinkle with 1/2 teaspoon of cinnamon. Layer the remaining bread pieces on top.
Whisk together the custard ingredients (including the remaining 1/2 teaspoon of cinnamon). Slowly pour the custard over the bread, saturating the top layer. The custard will not cover the top layer - the exposed bread cubes will still absorb the custard, but will also be a little toasty/crispy after baking, which adds a nice texture, a la pan-fried French toast.
Cover the dish with wrap and refrigerate for several hours, or overnight.
Preheat the oven to 425°F. Remove the dish from the fridge, and uncover.
Mix the topping ingredients in a small bowl, breaking up any clumps of brown sugar. Sprinkle over the top layer. Bake for 30 minutes or until puffy and golden. Serve with maple syrup, or even a fruit puree.
Cinnamon Eggnog Baked French Toast was originally published on https://soupaddict.com/cinnamon-eggnog-baked-french-toast/