Heat olive oil in a large skillet over medium heat. Add the onion and cook for about 3 minutes until softened. Add garlic and cook for 30 seconds until fragrant.
Add ground beef to the skillet. Cook and stir until browned and fully cooked, breaking it up as it cooks. Drain excess fat if needed.
Stir in hoisin sauce, soy sauce, rice vinegar, black pepper, and sesame oil. Reduce heat to low and simmer for 3 to 4 minutes until everything is well coated and heated through.
While the beef cooks, toast the pine nuts in a small skillet over medium heat. Stir constantly and cook for 2 to 3 minutes until lightly golden. Remove from heat immediately.
Spoon the ground beef mixture into lettuce leaves and sprinkle with toasted pine nuts. Serve right away.
Notes
Tips and Tricks
Browning the Beef - Break up the beef into small pieces as it cooks for the best texture.Toasting Nuts - Keep an eye on the pine nuts— they toast fast and can burn quickly.Serving - Serve everything family style so everyone can make their own wraps.
Storing and Reheating
Reheat on Stovetop – Place the beef mixture in a skillet with 1 to 2 tablespoons water. Warm over low heat, stirring until hot. Storing - Store any extra filling separately from the lettuce leaves in the fridge for up to 3 days. Lettuce is best fresh.