Preheat the oven to 425 degrees. Prepare three 17x11 inch baking sheets by lining them with parchment paper, setting them aside. Also line an 18x13 inch baking sheet with parchment paper and set aside.

Whisk together the pancake mix, eggs, and milk. Divide the batter evenly on the first two 17x11 baking sheets. Carefully tilt pans to spread the mixture evenly. Place in the oven and bake for 15 minutes. 

While the pancakes are cooking: In another large bowl combine the eggs, milk, salt, and pepper.  Pour the egg mixture onto the third 17x11 baking sheet. Place in the oven and bake for 15 to 17 minutes or until the eggs are set.

After the eggs have cooked, remove from the oven and decrease the oven temperature to 350 degrees. 

Press the sausage into the 18x13 baking sheet, covering the bottom in an even layer. Bake for 20 minutes. Drain the grease, patting with paper toweling if needed. Layer the cheese over the sausage and return to the oven and continue to bake for another 5 minutes or until the cheese has melted.

To assemble the sandwich, layer a pancake with the sausage and eggs, finishing with the second pancake. Portion into breakfast-sized sandwiches.

To freeze, wrap sandwiches individually and then place in an airtight container or freezer bags. Defrost the day before you need it. Reheat in the oven or microwave.