Heat the canola oil (for the veggies) in a pan over high heat. Cook the peppers, onion, salt, and pepper until soft and slightly caramelized.
2. Step
Transfer the cooked veggies to a bowl. In the same bowl, mix in the cream cheese, cheddar, and pepper jack, stirring until evenly incorporated. Set aside.
3. Step
In a separate bowl, combine the chicken with the salt, chili powder, cumin, and garlic powder, evenly distributing the spices over the chicken.
4. Step
On a cutting board, slice a pocket in the chicken horizontally.
5. Step
Fill the pocket with a heaping spoonful of the veggie mixture. Press the edges of the chicken together to seal in the filling. Repeat with the remaining chicken.
6. Step
Heat the canola oil in a pan over medium heat. Cook the stuffed chicken for five minutes on each side, until cheese is melted and chicken is cooked through.
