In Multipurpose Steamer, combine beef and seasoning. Cover; microwave on high, 3–5 min or until cooked through. Use Ground Meat Separator to break up large chunks. Drain any excess liquid.
Meanwhile, dice tomatoes, avocado, and onion.
To assemble, divide meat between 16 lettuce leaves, using 2 leaves for each wrap. Top with tomatoes, onion, and avocado. Add additional toppings, if desired.