Start your grill, broiler, or over an open flame on the stove top, char the outside of the poblano or pasilla chiles (not bell peppers) peppers completely. Place in a paper bag and seal for 10 minutes. Allow to steam, cool and then scrape off as much of the outer skin as you can.
For the roasted chiles (See Note 1), make a small incision down one side and open partially, keeping stem attached. Carefully remove any membrane threads and seeds. Set aside on lined baking sheet. For the bell peppers, slice pepper in half keeping stem attached, but remove seeds. Set aside.
Add the vegetable oil to a medium sauté pan over medium heat. Add the ground beef and brown, breaking up with spoon. Add the diced onion and cook until translucent, about 5 minutes. Add garlic, cumin and cook for about 5 minutes, season with salt to taste. Add salsa, corn, beans and simmer 5 minutes. When cooled slightly add half of the cheese and mix thoroughly.
Stuff each pepper with the beef mixture and set aside. Gently wrap the sides together so pepper encases filling. Divide cheese over the tops of each and bake for 20 minutes in a 350°F oven.
Top with more cheese (optional) and salsa of choice with chopped cilantro. Serve immediately.
1. Poblano or pasilla chiles, roasted until skin is blistered.