Step 1: Prep Your Ingredients. Gather all your ingredients. Dice any vegetables you plan to add, shred your cheese, and have your eggs cracked and whisked.
Step 2: Cook the Sausage. In a large skillet, cook the ground breakfast sausage over medium heat. Break it up with a spoon as it cooks until nicely browned and no pink remains. Drain any excess grease and transfer the cooked sausage to a bowl. Set aside.
Step 3: Scramble the Eggs. In the same skillet, melt a knob of butter over medium-low heat. Pour in your whisked eggs (with optional milk/cream). As the edges set, gently push cooked egg toward the center, allowing uncooked egg to flow underneath. Continue until eggs are mostly set but still slightly moist. Season with salt and pepper. Add the scrambled eggs to the bowl with the sausage.
Step 4: Combine the Filling. Add about three-quarters of the shredded cheese to the bowl with the cooked sausage and eggs. If using, mix in any cooked vegetables. Stir gently to combine.
Step 5: Warm the Tortillas. Warm large flour tortillas one at a time in a dry skillet over medium heat for 10-15 seconds per side, until pliable. Alternatively, microwave wrapped in a damp paper towel or warm in foil in the oven.
Step 6: Assemble the Burritos. Lay a warmed tortilla flat. Spoon about 1/2 to 3/4 cup of the filling mixture onto the center. Sprinkle with a little extra cheese.
Step 7: Roll Them Up. Fold in the sides of the tortilla over the filling, then tightly roll the tortilla upwards from the bottom to create a snug burrito.
Step 8: Repeat and Store. Continue assembling remaining burritos. If eating immediately, grill lightly in a dry skillet until golden. For meal prep, allow burritos to cool completely before individually wrapping in plastic wrap, then foil. Store in an airtight container or freezer bag.