Heat the oil in a large pan over medium high heat.
Place the ground beef in the pan and season with salt and pepper to taste. Cook for 6 8 minutes, breaking up the meat with a spatula.
Add the onion and cook for an addition 4 5 minutes.
Place the beef and onion mixture in the slow cooker along with the tomato sauce, ketchup, brown sugar, Worcestershire sauce, garlic powder, 1/2 teaspoon salt and 1/4 teaspoon pepper.
Stir to combine the ingredients.
Cook on HIGH for 3 hours or LOW for 6 hours.
Spoon the meat onto the hamburger buns then serve.
Slow Cooker Sloppy Joes · Dinner Match Lab | Dinner Match Lab