Heat olive oil in a large skillet or Dutch oven over medium-high heat. Add the diced onion and green bell pepper and cook, stirring occasionally, for 5 to 6 minutes until softened and beginning to turn golden at the edges.

Add the minced garlic and cook for 1 minute until fragrant, stirring constantly to prevent burning.

Add the ground beef to the skillet, breaking it apart with a wooden spoon or spatula. Cook over medium-high heat for 7 to 9 minutes until fully browned with no pink remaining. Drain any excess fat if needed.

Stir in the tomato paste and cook for 2 minutes, stirring constantly, until the paste darkens slightly and coats the meat — this step deepens the flavor significantly.

Add the crushed tomatoes, ketchup, Worcestershire sauce, yellow mustard, brown sugar, apple cider vinegar, and smoked paprika. Stir well to combine everything thoroughly.

Reduce heat to medium-low and simmer the filling uncovered for 15 to 18 minutes, stirring occasionally, until the sauce thickens to a scoopable consistency. Taste and adjust salt, pepper, and sugar as needed.

Remove from heat and allow the filling to cool completely. Transfer to an airtight container or heavy-duty zip-lock bags and refrigerate for up to 3 days, or freeze for up to 3 months.

Set a cast iron skillet or camp pot on a stable grill grate over medium campfire heat. Add the chilled Sloppy Joe filling directly to the pan.

Stir occasionally and heat for 8 to 12 minutes until the filling is piping hot throughout. If it has thickened during storage, stir in a splash of beef broth or water to loosen it to your desired consistency.

While the filling heats, toast the buns cut-side down on the grill grate for 60 to 90 seconds until golden and lightly charred.

Spoon generous portions of the hot filling onto the toasted buns and top with your choice of dill pickles, cheddar cheese, or creamy coleslaw. Serve immediately and enjoy.