Step 1

Arrange a rack in the middle of the oven and heat the oven to 375ºF. Coat a 9x9-inch square or shallow 2-quart baking dish with cooking spray.

Step 2

Open 2 (12.5-ounce) tubes refrigerated cinnamon rolls. Separate the rolls and reserve the icing. Using kitchen shears or a pizza cutter, cut each cinnamon roll into 4 pieces. Arrange them in an even, single layer in the baking dish (they can be squished together).

Step 3

Place 1/2 cup whole milk, 1/4 cup maple syrup, 4 large eggs, 2 teaspoons vanilla extract, and 2 teaspoons ground cinnamon in a medium bowl and whisk to combine. Pour over the cinnamon rolls. Press down gently on the cinnamon rolls to make sure all are evenly soaked in the egg custard.

Step 4

Bake until the custard is set and the top is golden brown, 25 to 32 minutes. Place the baking dish on a wire rack and let the casserole cool slightly. Transfer the icing from both containers to a small microwave-safe bowl. Microwave on HIGH in 5-second intervals, stirring between each, until thin enough to drizzle, 10 to 15 seconds total. Drizzle the icing over the casserole.