Season steak with salt, pepper, chili powder, cumin, and garlic powder. Heat olive oil in a skillet over medium-high heat. Sear steak for 3-4 minutes on each side until cooked to your liking. Let rest, then slice thinly.

In the same skillet, add more olive oil if needed. Sauté sliced bell pepper and onion over medium heat for 5-6 minutes until softened. Season with salt and pepper.

Clean the skillet, reduce heat to medium, and melt butter. Place one flour tortilla, add cheese, sliced steak, sautéed vegetables, and more cheese. Fold tortilla in half.

Cook quesadilla for 2-3 minutes on each side until golden brown and cheese melts. Monitor cooking to prevent burning.

Let quesadilla rest for 1 minute, then slice into wedges and serve hot with dipping sauces.