Begin by finely chopping the onion and green bell pepper. Heat a large skillet over medium heat and add a splash of oil. Sauté the onion and bell pepper for about 5 minutes until they become soft and translucent.

Add the ground beef to the skillet, breaking it apart with a spatula. Cook for about 7-10 minutes, or until the beef is browned and fully cooked. Drain any excess fat if needed.

Once the beef is browned, stir in the ketchup, mustard, Worcestershire sauce, brown sugar, and Sloppy Joe seasoning. Mix well and let the mixture simmer for about 5 minutes.

While the filling simmers, slice the burger buns in half and place them cut-side up on a baking sheet. Toast them in a preheated oven at 350°F for about 5-7 minutes.

Spoon the flavorful beef mixture onto the toasted bun bottoms. Top with cheddar cheese if desired. Finish with pickles or coleslaw.

Serve the Classic Sloppy Joes immediately while they're warm. Enjoy with a side of crispy chips or salad.