How to Make It
Cook sirloin in a large cast-iron skillet coated with cooking spray over medium-high, stirring occasionally to crumble, until browned, 7 to 9 minutes. Add bell pepper, poblano, and onion; cook, stirring occasionally, until tender, 3 to 4 minutes. Stir in salt and desired amount of chipotle peppers. Smooth surface of mixture, and top with cheese slices. Cook until cheese is mostly melted. Using a spatula, “chop” cheese to incorporate into mixture.
Divide sirloin mixture among tortillas. Top evenly with lettuce, tomatoes, and sour cream.