Carefully remove the butter lettuce leaves from the head of lettuce, wash with cool water, and set out to dry on a towel.
Next, assemble the dipping sauce: In a small bowl, whisk together the lime juice, fish sauce, sugar, and 1 of the sliced peppers. Season lightly with salt and pepper and set aside.
In a large skillet, heat the olive oil over medium-high heat. Add the ground pork and cook, stirring occasionally, until browned (about 10 minutes or so). Add the garlic and cook for a few minutes, until softened and fragrant.Turn off the heat and season with salt and pepper. Stir in the onion, basil, cilantro, mint, and remaining pepper slices.
Serve family style, with the pork mixture, lettuce leaves, and dipping sauce. To assemble, spoon the pork into a lettuce leaf and either dip the wraps into the sauce or spoon over the top before eating.