Make the cinnamon rolls (skip steps 1-7 if you use store-bought rolls).

Prepare the dough by whisking the flour, sugar, and salt in a large mixing bowl, then set it aside.

In a deep pan, combine the milk and butter and heat on the stove until the butter melts and the mixture is warm but not hot (104°F/40°C). Stir in the yeast until it fully dissolves.

Add this liquid mixture to the set-aside dry ingredients along with the egg. Combine with a spatula, or a stand mixer fitted with a paddle attachment on medium speed, until a soft, pliable dough forms.

Turn the dough onto a floured surface and knead with floured hands for about 5 minutes, until it forms a smooth ball. Add a little more flour if the dough feels overly sticky or soft.

Place the dough in a lightly greased bowl and cover it loosely. Let it rest for about 10 minutes while you prepare the filling.

For the filling, roll the rested dough into a rectangle measuring roughly 12 x 8 inches (30 x 20 cm). Spread the softened butter over the surface, then sprinkle the cinnamon and brown sugar evenly on top.

Carefully roll the dough into a log and slice it into 8 equal portions. Arrange the rolls in a greased round baking pan.

Let the rolls rise by covering the pan with a clean towel and placing it in a warm spot for 60 minutes, until they have doubled in size.

Heat the oven to 180°C (356°F).

In a bowl, whisk the eggs, milk, vanilla, and cinnamon until well combined.

Pour the egg mixture evenly over the rolls, then drizzle with the maple syrup.

Bake the cinnamon roll casserole in the hot oven for 30 minutes, or until well browned on the surface.

Mix the glaze ingredients in a bowl.

Serve the cinnamon roll casserole hot, drizzled with the glaze.