In a skillet on medium-high, warm canola oil. Add ground beef, onion and mushrooms. Stir, breaking up beef with back of spoon, until fully cooked.
In a small bowl mix garlic, soy sauce, hoisin sauce, ginger, rice wine vinegar and sriracha sauce. Pour over meat mixture and heat through.
Remove from heat and stir in green onion and sesame oil.
Serve on lettuce leaf topped with peanuts (if using) and additional sriracha sauce.