Preheat the broiler and place the red pepper, tomato and onion under it until cooked to your desired taste. I love it when their super crispy!
Meanwhile, mix together the Greek yogurt, lime juice, chili powder, cayenne pepper, salt and hot sauce. Spread evenly on the tortilla.
Place the lettuce on top of the tortilla and add the roasted vegetables. Top with the slice of roast beef, roll it up and serve!