Heat the olive oil over medium heat in a cast-iron skillet.
Add the onion, jalapeno, and chicken to the skillet. Occasionally stir and crumble the chicken with a metal spatula as it cooks. It will take 10-15 minutes to thoroughly cook the chicken.
As the chicken mixture cooks, prepare the mini bell peppers by removing the tops, cutting in half lengthwise, and removing the seeds. Lay the peppers out in a single layer in a large roasting pan or two air fryer trays.
After the chicken is cooked, stir in the beans, salsa, chili powder, and salt. Make sure the mixture is thoroughly combined.
Stuff the mini bell pepper halves with the chicken and bean mixture.
Cover the stuffed pepper halves with the cheese. The peppers should be tightly packed on the pan, so no need to get fussy about carefully covering each pepper. You are making a cheese blanket here!
Air Fryer Directions: Air fry the peppers for 9 minutes at 350°F (175°C). Air fry one tray of peppers at a time in the top rack position of the air fryer oven (closest to the heating element).
Oven Directions: Broil the peppers on high for about 3 minutes. The cheese will melt and brown a bit.
Garnish the finished taco-stuffed mini bell peppers with chopped cilantro. Admire the cheese pull as you remove them from the tray!