Step 1: In a bowl, whisk together eggs, milk, salt, and pepper until well combined. Set aside.
Step 2: Heat olive oil in a large skillet over medium heat. Add sausage and cook, breaking it up with a spoon, until browned and cooked through (about 5-7 minutes).
Step 3: Add diced onion and bell pepper to the skillet with the sausage. Cook, stirring occasionally, until vegetables are softened (about 5 minutes).
Step 4: Pour the egg mixture into the skillet. Cook, stirring gently, until eggs are scrambled and fully set (about 3-4 minutes). Remove from heat.
Step 5: Lay out tortillas on a clean surface. Divide the egg-sausage mixture evenly among the tortillas, placing it in the center of each.
Step 6: Sprinkle shredded cheese evenly over the filling on each tortilla.
Step 7: Fold the sides of each tortilla inward, then roll tightly from the bottom to form a burrito.
Step 8: Wrap each burrito individually in foil or plastic wrap. Store in the refrigerator for up to 3 days or freeze for up to 1 month.
Step 9: To serve, unwrap and reheat in a microwave for 1-2 minutes or in a skillet over medium heat until warmed through. Serve with salsa or hot sauce if desired.