Place beef in a large resealable plastic bag. Whisk together marinade ingredients in a medium bowl (garlic through chili paste) and pour over the beef. Seal tightly and marinade for 30 minutes or overnight.
When you're ready to prepare the lettuce wraps, pre-heat grill to high heat. Grill steak about 4 minutes per side for medium rare. (Longer if you prefer well done.) Remove steak from grill and let rest 10 minutes before slicing.
While steak is grilling, whisk together the peanut dipping sauce: RXBar Peanut Butter through chili paste; set aside.
When meat is done resting, thinly slice against the grain. Place a slice of meat inside the lettuce leaves and garnish with optional toppings. Dip or drizzle with peanut sauce to serve.