Start by preheating your oven to 375°F. Spray a 9×13 pan with nonstick baking spray and set aside.

In your large bowl, whisk together the oats, salt, baking powder, cinnamon, and most of the toasted walnuts, reserving a handful for topping later. Pour this mixture into your prepared pan.

In a separate bowl, beat the eggs, then add the milk, heavy cream, maple syrup, and vanilla extract. Stir until well incorporated.

Carefully pour the liquid mixture over the oat mixture in your baking dish. Stir with a fork to ensure there are no dry spots.

Bake uncovered for 45-55 minutes until all the liquid has been absorbed and the top is golden brown.

While your oatmeal bars are baking, prepare the frosting. Combine room-temperature cream cheese, vanilla, heavy cream, and powdered sugar in a bowl. Mix on low speed until smooth. Transfer this mixture to a piping or ziplock bag.

Once the bars have baked, allow them to cool for 10-15 minutes. Then, top with the cream cheese frosting and the reserved toasted walnuts.

Slice your Cinnamon Roll Baked Oatmeal Bars into servings, and enjoy a breakfast that feels like a treat!