Cube bread (at least an hour ahead of time if possible) and spread out on a baking sheet to harden.
When you’re ready to assemble, grease an 8”x8” baking dish and layer half the bread cubes in the bottom.
Cream together cream cheese, powdered sugar, and vanilla and dollop evenly over bread. Top with remaining bread cubes.
Whisk together eggs, milk, brown sugar, vanilla, and cinnamon. Pour evenly over bread cubes, making sure the entire top is soaked. At this point, the dish can be covered with plastic and refrigerated until ready to bake.
Preheat oven to 350°.
Whisk together flour, brown sugar, and cinnamon in a small bowl. Use your fingertips to cut in cold butter until the mixture is coarse and sprinkle over the dish.
Bake at 350° for 45-50 minutes until golden brown. Drizzle with maple syrup if desired and serve immediately.