Cook sausage in a skillet over medium heat until browned and no longer pink. Drain excess fat.

Stir in condensed cream of potato soup into the cooked sausage.

In a separate mixing bowl, beat eggs, milk, and pepper together.

Stir the sausage and soup mixture into the egg mixture.

Add chopped cilantro, diced green chilies, and diced onion to the mixture. Stir until well combined.

Transfer the mixture to a lightly greased 11-in x 7-in x 2-inch baking dish.

Sprinkle shredded cheddar cheese evenly over the top.

Bake uncovered at 375°F (190°C) for 40-45 minutes, or until a knife inserted near the center comes out clean.