Preheat the oven to 350°F (175°C).
Cut the bread into 1-inch cubes and place half of them in the greased 9x13-inch baking dish.
Scatter half of the sliced strawberries over the bread cubes.
Repeat with the remaining bread cubes and strawberries, layering them in the baking dish.
In a large mixing bowl, whisk together the eggs, milk, granulated sugar, vanilla extract, cinnamon, and salt until well combined.
Pour the egg mixture evenly over the layered bread and strawberries, making sure all pieces are soaked.
Using a spatula, gently press down the bread to ensure it's submerged in the custard.
Drizzle the melted butter over the top of the casserole.
Cover the baking dish with aluminum foil and let it sit for 15 minutes while the oven preheats.
Bake in the preheated oven for 25 minutes covered, then remove the foil and bake for an additional 10 minutes, or until the top is golden brown and the custard is set.
Allow to cool slightly before serving. Dust with powdered sugar and serve with maple syrup.