Cut the tortillas into medium-sized squares.

Heat enough vegetable oil in a skillet and fry the tortilla pieces until crispy.

In a separate pot, bring the tomatoes and chiles to a boil. Once boiling, remove the tomato skins and transfer the tomatoes and chiles to a blender along with the garlic, onion, and cilantro. Blend until smooth.

In a saucepan, add a splash of oil and sauté sliced onion. Pour in the blended sauce, season with salt to taste, and cook for a few minutes.

Meanwhile, season the steak and grill it until cooked to your liking.