Into a medium-size skillet over medium heat, add the olive oil. When the oil is hot, add the vegan ground beef, onion, and pepper.
Cook for 5 minutes, stirring occasionally until the vegan beef is browned and vegetables are softened.
Stir in the ketchup, brown sugar, mustard, garlic powder, salt, and pepper.
Reduce heat to low simmer 20 minutes, stirring occasionally.
Pile the sloppy joe mixture onto toasted burger buns and serve warm.