Gather all ingredients. Preheat the oven to 350 degrees F (175 degrees C). Grease an 8x8-inch baking pan.
Line the bottom of the prepared pan with bread cubes.
Beat milk, eggs, 2 tablespoons sugar, salt, and vanilla together in a large bowl until well combined; pour over bread cubes and stir to coat. Dot with butter; let stand for 15 minutes.
Combine remaining 2 tablespoons sugar with cinnamon; sprinkle over top of casserole.
Bake in the preheated oven until the center is set and top is golden, about 45 to 50 minutes.
Serve and enjoy!
