Turkey Fajita Wraps

3 tablespoons canola oil

1 small red onion, thinly sliced

1 red bell pepper, cored, seeded, and thinly sliced

1 green bell pepper, cored, seeded, and thinly sliced

1 clove garlic, minced

1 pound skinless, boneless turkey breast, cut into thin strips

1/2 tablespoon ground cumin

1/2 tablespoon chili powder

1/2 teaspoon kosher salt

1/4 teaspoon freshly ground black pepper

2 dashes cayenne pepper

6 large red leaf lettuce leaves

2 tablespoons finely chopped cilantro leaves

4 ounces shredded Colby Jack cheese, Monterey Jack, or Cheddar

1/4 cup sour cream