Cook the sausage: In a nonstick skillet over medium heat, crumble and brown the pork sausage, breaking it into small pieces. Add the diced onion and sauté for 3–4 minutes until the sausage is fully cooked and onions are translucent. Drain excess grease.
Add chiles: Stir in the green chiles and cook for 1 more minute to warm through.
Scramble the eggs: Pour the beaten eggs into the skillet with the sausage mixture. Season lightly with salt and pepper. Gently scramble with a rubber spatula until the eggs are just set but still moist. Remove from heat.
Warm tortillas: Wrap tortillas in a damp paper towel and microwave for 20–30 seconds until pliable.
Assemble burritos: Place one slice of American cheese (torn in half if needed) in the center of each tortilla. Spoon ¼ of the egg-sausage mixture over the cheese.
Roll: Fold the bottom edge up over the filling, tuck in both sides, and roll tightly into a cylinder, leaving the top slightly open.
Serve: Enjoy immediately with salsa, sour cream, or hot sauce on the side. For meal prep, wrap cooled burritos in foil or parchment and freeze. Reheat in microwave or skillet before serving.
