1 tablespoon vegetable oil
1 large white onion, sliced
3 Roma tomatoes, cored & sliced lengthwise from the center
3 Serrano chiles, sliced lengthwise into thin strips
1 tablespoon chopped cilantro
salt and black pepper to taste
1. Slice the skirt steak, across the grain, into 1" strips.
2. Place the oil in a large frying pan over medium-high heat. When it starts to sizzle, add the steak and brown on all sides.
3. Add the onion, tomato, and chiles. Cover, stirring occasionally until the meat is cooked, 4-5 minutes. Sprinkle with cilantro, salt, and pepper.