01 - Grease a 9x13-inch baking dish generously with cooking spray or softened butter, ensuring all surfaces are evenly coated to prevent sticking.
02 - Arrange the pancakes in the prepared baking dish in a single layer, overlapping them slightly to cover the entire bottom. Brush the tops evenly with the melted butter.
03 - In a medium mixing bowl, whisk together the eggs, whole milk, heavy cream, salt, black pepper, ground cinnamon, and vanilla extract until fully combined and smooth.
04 - Scatter the cooked sausage or bacon, shredded cheddar cheese, and fresh berries evenly across the pancake layer, distributing the ingredients so every portion gets a balanced mix.
05 - Slowly pour the egg custard mixture over the pancakes and fillings, tilting the dish gently to ensure the liquid seeps into every crevice and coats everything evenly.
06 - Cover the dish tightly with plastic wrap or aluminum foil and refrigerate for at least 4 hours, preferably overnight, allowing the pancakes to fully absorb the custard.
07 - Preheat the oven to 350°F (175°C). Remove the baking dish from the refrigerator, uncover it, and let it stand at room temperature while the oven comes to full temperature.
08 - Drizzle 2 tablespoons of maple syrup evenly over the surface of the casserole before baking.
09 - Bake uncovered for 40 to 45 minutes, until the top is golden brown, the edges are puffed, and the center is fully set with no liquid custard remaining.
10 - Remove from the oven and let the casserole rest for 10 minutes before slicing into portions. Dust with powdered sugar and garnish with additional fresh berries or sliced bananas. Serve warm with extra maple syrup on the side.