Ingredients

• 2 tablespoons butter, melted
• 1 tablespoon Muir Glen™ organic tomato paste
• 1/2 teaspoon salt
• 2 cups thinly sliced onions
• 8 oz mushrooms, thinly sliced (about 3 cups)
• 1 cup Progresso™ beef flavored broth (from 32-oz carton) Save $
• 1 lb lean (at least 80%) ground beef
• 1/2 cup Progresso™ plain panko crispy bread crumbs
• 1/3 cup milk
• 1 egg, slightly beaten
• 1 tablespoon Montreal steak grill seasoning
• 1 tablespoon soy sauce
• 2 tablespoons cornstarch
• 2 tablespoons cold water
• 1 pouch (4.7 oz) Betty Crocker™ creamy butter mashed potatoes, made as directed on pouch
• 2 tablespoons chopped fresh Italian (flat-leaf) parsley leaves

Steps
1-Spray 5- or 6-quart oval slow cooker with cooking spray. Mix melted butter, tomato paste and salt in slow cooker. Add onions and mushrooms; toss to coat. Stir in broth.
2-In large bowl, mix beef, bread crumbs, milk, egg, grill seasoning and soy sauce. Shape into about 24 (1 1/2-inch) meatballs. Place meatballs in slow cooker on top of vegetable mixture.
3-Cover; cook on Low heat setting 3 to 4 hours or until meatballs are thoroughly cooked (165°F); stir. In small bowl, beat cornstarch and cold water. Quickly stir into slow cooker; cover. Increase to High heat setting; cook 5 to 10 minutes or until thickened. Serve over mashed potatoes. Sprinkle with parsley.
source:https://www.bettycrocker.com