Heat 3 tablespoons olive oil in a large skillet over medium heat until shimmering. Add the sliced yellow onion and sauté about 5 minutes, stirring occasionally, until the onion begins to sweat and becomes translucent.
Add the red and green bell pepper strips to the skillet. Continue sautéing 5–7 minutes, stirring occasionally, until the peppers are tender but still slightly crisp.
Add the minced garlic and cook 30–60 seconds, stirring, until fragrant.
Add the 1 pound ground turkey, 2 teaspoons chili powder, 2 teaspoons ground cumin, 1 teaspoon paprika, and ½ teaspoon salt. Break the turkey into small, bite-sized pieces with your spatula, stir to combine with the vegetables and spices, and cook 5–8 minutes, stirring frequently, until the turkey is cooked through and no pink remains.
Separate the butter leaf lettuce leaves, rinse and pat them dry. Spoon the desired amount of the turkey–veggie mixture onto each lettuce leaf.
Top each wrap with cheese and any other toppings from the ingredient list, fold or roll the lettuce around the filling, and serve immediately.