In a large bowl, add the ground beef, breadcrumbs, ketchup, egg, fresh garlic, mustard and Worcestershire sauce. Season it with salt and pepper and garlic powder and mix everything together just until it’s evenly combined.
Roll the mixture into even sized balls and place them onto a parchment paper lined baking sheet. Place the baking sheet into the center wrack of the oven for 25-30 minutes.
While that’s cooking, in a large skillet, sauté the chopped onion and mushrooms in a little olive oil until soft. Lightly season then with salt and pepper.
Whisk in the butter and flour for 2-3 minutes. It will make a thick paste.
Slowly whisk in the beef broth.
Stir in the ketchup, Worcestershire sauce and Kitchen Bouquet. Season the gravy with salt, pepper and garlic powder and turn the heat down to a simmer.
Add the cooked meatballs into the skillet and spoon the gravy over them.
Sprinkle the meatballs with some fresh parsley, serve warm over Sour Cream Mashed Potatoes (optional) and enjoy.