Heat the oil In a skillet over medium high heat. Add the onions and peppers and saute about 2 minutes, until just starting to soften. Push the veggies over to the side and add the ground beef, spreading it out over the pan. Cook, undisturbed, for a few minutes until the beef starts to brown. Break the beef into smaller pieces and continue to cook the beef and veggies together, stirring occasionally, until no pink remains. Season to taste with salt and pepper. If you have more than a Tablespoon of fat in the pan, drain it off.

In a slow cooker, combine the cooked beef and veggies and all the remaining ingredients, up to the rolls. Stir to combine. Set the crock pot to low and cook for 2-3 hours. The crock pot can then be set to warm and kept on warm for another 1-2 hours.

To serve, pile the sloppy joe mixture onto the buns. Top with the cheese, pickles, and onions.