Step 1

Make the casserole: Generously coat a 9x13-inch baking dish with butter. Place the bread cubes evenly in the dish and set aside.

Step 2

Place the eggs in a large bowl and whisk to combine. Whisk in the half-and-half, pumpkin, sugar, pumpkin pie spice, vanilla, and salt. Evenly pour the custard over the bread. Use a spoon to push the bread down and stir so all the cubes are soaked through. Cover tightly with plastic wrap and refrigerate overnight.

Step 3

Arrange a rack in the middle of the oven and heat to 350°F. Remove the baking dish from the refrigerator and let it sit at room temperature while the oven is heating. Meanwhile, make the crumb topping.

Step 4

Make the crumb topping: Stir the flour, sugar, pecans, cinnamon, nutmeg, and salt together in a medium bowl. Drizzle with the butter and stir until big, slightly floury crumbs form.

Step 5

Sprinkle the crumb topping over the casserole. Bake uncovered until the casserole is set, puffed, and the top is golden-brown, 40 to 45 minutes.

Step 6

Remove the baking dish from the oven and let it cool for at least 5 minutes. Right before serving, dust with powdered sugar if desired. Serve warm with maple syrup if desired.