Start by browning the sausage in a skillet over medium heat for about 8–10 minutes, breaking it into bite-sized pieces as it cooks. Ensure it’s completely cooked through and reaches an internal temperature of 160°F (71°C). Once done, drain any excess fat and set the sausage aside to cool slightly while you prepare the batter.

In a mixing bowl, combine the pancake mix, eggs, milk, salt, and pepper. Whisk together until the mixture is smooth and free of lumps. The batter should have a slightly thick consistency to hold everything together.

Preheat your oven to 350°F (175°C). Grease a 9x13-inch baking dish to prevent sticking. Begin layering by placing half of the cooked sausage in the bottom of the dish. Pour half of the pancake batter over the sausage, followed by half of the shredded cheese. Repeat these layers with the remaining sausage, batter, and cheese.

Cover the layered casserole with plastic wrap or aluminum foil and place it in the refrigerator. Allow it to chill overnight.

In the morning, remove the casserole from the refrigerator and uncover it. Bake in the preheated oven for 40–45 minutes, or until the top is golden brown and the center is set.

Once baked, remove the casserole from the oven and let it cool for about 10 minutes. Cut into squares and garnish with chopped herbs if desired, then serve warm.