Preparation

• Whisk the egg in a large bowl then add the onions, garlic, ketchup, Dijon mustard, Worcestershire sauce, salt, pepper and parsley and stir to combine.
• Add the ground beef and breadcrumbs and gently stir but do not overmix.
• Form 18-25 balls from the meat mixture then heat the olive oil in a large skillet over medium heat.
• Add half of the meatballs to the pan and gently stir to prevent burning and cook for about 5 minutes or until all sides have turned a dark brown color.
• Remove the meatballs from the pan and repeat the cooking process with the remaining half of the meatballs.
• Once all the meatballs have been cooked, make the gravy by adding the butter to the pan along with the mushrooms and stir and cook for about 5 minutes or until the mushrooms have reduced significantly.
• Add the flour and stir and cook just until the flour starts to turn a dark brown color.
• Stir in the Dijon and Worcestershire sauce then pour in the beef broth 1 cup at a time, whisking between each addition.
• Continuously whisk over medium heat until the gravy starts to thicken then add the meatballs back to the gravy, reduce the heat to low medium then cover with a lid and let it simmer for 15 minutes.
• Remove the pan from the heat and serve over mashed potatoes and garnish with freshly minced parsley if desired.