Step 1

Mix half-and-half, eggs, vanilla, and 1 tablespoon dark brown sugar together in a large shallow bowl; add French bread. Cover bowl with plastic wrap and refrigerate 8 hours to overnight.

Step 2

Preheat oven to 350 degrees F (175 degrees C).

Step 3

Place butter in a 9x13-inch casserole dish. Place casserole dish in the preheating oven to melt butter, about 5 minutes. Swirl butter over bottom of the dish.

Step 4

Spread brown sugar, maple syrup, and pecans over the melted butter. Arrange soaked bread atop pecan mixture.

Step 5

Bake in the preheated oven until French toast is cooked through, 30 to 35 minutes. Sprinkle with confectioners' sugar.