1. In a bowl, mix tahini paste, garlic, lemon juice, and salt to taste. Set aside.
2. In a pot, combine lentils and water and cook until water disappears. Set aside.
3. In a frying pan, heat oil and sauté red onion until soft. Add lentils. Add barbecue sauce and toss to combine. Cook on low for a few minutes.
4. In a bowl, place shredded cabbage, juice of the lime, and salt to taste. Mix until combined.
5. To assemble burritos: Lay tortilla on a plate. Load with lentils, beans, slaw, and avocado and drizzle some tahini. Fold over the bottom and top of the tortilla and then roll as tightly as possible. Cut in half if desired. Repeat with remaining tortillas.
6. Serve burritos with extra tahini dressing.