Preheat your oven to 175°C (350°F) and grease a 23 x 33 cm (9×13 inch) baking dish with butter.

In a deep skillet over medium heat, cook the ground beef until browned, about 5–7 minutes. Drain excess grease.

Add the diced onion and green bell pepper to the skillet, cooking until the onion is translucent, about 5–8 minutes.

Stir in the ketchup, mustard, Worcestershire sauce, and brown sugar, seasoning with salt and black pepper to taste. Cook for an additional 2–3 minutes.

Gently fold in the pork and beans, incorporating them without breaking them.

Pour the beef and bean mixture into the prepared baking dish and cover tightly with aluminum foil.

Bake in the preheated oven for approximately 45 minutes until bubbling around the edges.

Remove from the oven and let it rest for about 10 minutes before serving.