To make the French toast, grease a 9x13-inch baking dish.
Slice the bread into 15 pieces. Each piece will be about 1" thick.
Arrange the slices in the bottom of the baking dish. You want don't want to fit the bread in too tightly because the bread will puff up as it bakes.
In a large bowl, add the eggs, milk, sugar, and vanilla.
Whisk until well-combined.
Pour the egg mixture over the bread slices, gently pressing the bread in as needed.
Cover with plastic wrap, and chill overnight.
Remove from the fridge while you preheat the oven.
Preheat the oven to 350F.
To make the topping, stir together the melted butter, brown sugar, pecans, corn syrup, and cinnamon.
Spoon the praline mixture over the bread.
Bake for 40-55 minutes, or until the French toast is puffed and golden brown. The center should be set.
Serve as-is or topped with maple syrup.
French bread: French or Italian bread will work for this recipe. I don't remove the crust.
Milk: You can use any milk from skim milk to whole milk. You can also use nondairy milk, like almond milk. If you want richer French toast, feel free to substitute part or all of the milk with half-and-half.
Butter: I use salted butter in this recipe. If you use unsalted butter, add a pinch or two of salt.
Brown sugar: I use light brown sugar. However, you can use dark brown sugar for a richer praline sauce.