If using raw steak, season it generously with salt, pepper, chili powder, cumin, and garlic powder. Heat one tablespoon of olive oil in a large skillet over medium-high heat. Cook the steak for 3-4 minutes per side until it reaches your desired doneness. Remove from heat and let it rest for 5 minutes before slicing thinly against the grain.

While the steak rests, add the remaining tablespoon of olive oil to the same skillet. Sauté the sliced bell pepper and onion over medium heat for 5-6 minutes until softened and slightly caramelized. Season with a pinch of salt and pepper. Remove vegetables from the skillet and set aside.

Wipe the skillet clean and reduce heat to medium. Add a small pat of butter to the pan. Place one tortilla in the skillet and immediately sprinkle half of it with about ½ cup shredded cheese. Layer with sliced steak, sautéed vegetables, and another ¼ cup cheese. Fold the tortilla in half.

Cook for 2-3 minutes until the bottom is golden brown and crispy. Carefully flip the quesadilla and cook for another 2-3 minutes until the second side is equally crispy and the cheese has melted completely.

Transfer to a cutting board and let rest for one minute before slicing into wedges. Repeat with remaining tortillas and filling ingredients.