In a small bowl combine softened cream cheese, shredded pepperjack cheese, bell pepper, chopped onion, garlic powder, and onion powder. Mix well.
Using a sharp knife, slice through the middle of each chicken breast lengthwise (not all the way through) to create a pocket to stuff the filling into. I leave at least a half inch on each end unsliced so that the filling does not fall out.
Spoon filling into each chicken breast, dividing filling evenly between them. (If you have extras you can spread it over the top of the chicken after searing in the pan before it goes in the oven.) Using toothpicks or skewers, pin the edges of the chicken shut at a diagonal angle.
Combine ingredients for dry rub (cumin, garlic, chili powder, salt, and pepper) and sprinkle over both sides of each chicken breast carefully.
Heat a large oven safe frying pan (I use cast iron) over medium heat, and add olive oil. If you don't have an oven safe frying pan just use a normal one, then transfer the chicken to baking dish. Sear chicken for about 4 minutes on each side, making sure they do not burn. Any extra filling can be spread on chicken breasts at this point.
Immediately transfer to preheated oven (if using a regular frying pan transfer to oven safe baking dish) and bake at 400 F for 15-18 minutes, or until instant read thermometer in thickest part of breast reads at least 165 F. Remove from oven, cover pan in foil, and let rest 5 minutes before serving.
Notes
The size of chicken breasts will determine cooking time needed. Smaller chicken breasts will need less time and larger may need more time. Freezing instructions: Freeze raw individually wrapped for up to three months. Thaw completely in refrigerator before cooking.