Preheat the oven to 350 degrees F (175 degrees C)
Lightly grease a 9x13-inch baking dish
Heat a large skillet over medium-high heat and cook sausage until browned and crumbly, 5 to 7 minutes
Drain and discard grease from sausage and set aside to cool slightly
Place bacon in a large skillet and cook over medium-high heat, turning occasionally, until evenly browned and crisp, about 10 minutes
Drain bacon slices on paper towels and crumble when cool enough to handle
Whisk together pancake mix and water until well combined
Stir in maple syrup
Add sausage, bacon, and cheese and fold the mixture together until well incorporated
Pour mixture into prepared baking dish
Bake in the preheated oven until casserole is lightly browned and a toothpick inserted near the center comes out clean, about 30 minutes
Spread butter over hot casserole and serve with extra syrup as desired
