Open both cans of cinnamon rolls and cut each roll into quarters. You’ll end up with bite-sized pieces that bake evenly and absorb flavor better. Scatter them across your baking dish.
In a large bowl, whisk the eggs, milk, cream, maple syrup, vanilla, cinnamon, nutmeg, and salt.
Pour the custard mixture evenly over the cinnamon roll pieces. Make sure all pieces get coated. Some will float, some will sink; don’t overmix or press anything down.
Let everything sit for 8–10 minutes.
Place the dish into the oven and bake for 32–38 minutes.
The top should turn golden brown while the center remains slightly soft but not liquid. If the edges start to brown too quickly, cover lightly with foil for the last 10 minutes.
Let the casserole cool for 10–15 minutes. If you drizzle icing immediately, it melts into the casserole. If you wait, it holds its shape better on top — choose whichever finish you prefer.