Grease the inside of your slow cooker with 2 tablespoons of melted unsalted butter.

Cut each refrigerated cinnamon roll into four equal quarters and arrange in a single layer in the slow cooker.

In a large bowl, whisk together eggs, heavy cream, whole milk, maple syrup, vanilla extract, ground cinnamon, and salt until smooth.

Pour the custard mixture over the cinnamon roll pieces and gently press down to submerge them.

Cover the slow cooker and cook on High for 2.5 hours or Low for 6-8 hours until set and golden brown.

In a microwave-safe bowl, heat the cream cheese icing and melted butter until fluid, then drizzle over the casserole.