To make the sauce; in a saucepan over medium heat, combine all the ingredients. Stir and heat until well blended, then turn down to low and let simmer until meat mixture is ready.

To make filling; cook ground meat until fully cooked (drain off any fat if necessary). Add remaining ingredients, and cook until heated throughout (or until veggies are cooked to your likeness). Stir in 1/2-3/4 of the sauce (reserve some for serving), and place into a serving bowl.

To serve; set out individual bowls of reserved sauce, filling mixture, and toppings.

To eat; take a lettuce leaf, fill with a few tablespoons of filling, add any toppings and extra sauce you'd like, then gently fold lettuce leaf around burrito-style.