2Transfer the browned meatballs to your slow cooker.
3Soften two onions in the same pan used for the meatballs.
4Add the softened onions, tomato purée, Worcestershire sauce, mustard, oregano, onion granules, garlic, beef stock, and Bistro gravy (mixed with water) to the slow cooker with the meatballs.
5Cook on high for 4 hours or on low for 7-8 hours.
6Serve with creamy, buttery mashed potatoes and greens, garnished with thyme.