Preheat the oven to 375°F (190°C).
In a large skillet over medium heat, cook the ground beef and diced onion until the beef is browned and the onion is tender. Drain any excess fat.
Stir in the ketchup, brown sugar, Worcestershire sauce, garlic powder, and black pepper. Cook for an additional 5 minutes, allowing the flavors to meld.
Open the can of biscuit dough and cut each biscuit into quarters. Add the biscuit pieces to the skillet and gently stir to coat them with the sloppy joe mixture.
Pour the entire mixture into a greased 9x13-inch baking dish and spread it evenly.
Sprinkle the shredded cheddar cheese on top of the casserole.
Bake in the preheated oven for 20-25 minutes or until the biscuits are golden brown and cooked through.
Once done, remove from the oven and let it cool for a few minutes. Garnish with fresh chopped parsley before serving.