Heat oven to 375°F. In a large bowl combine ground meat, onion, garlic, egg, mustard, breadcrumbs and salt. Form into 20 1½-inch balls and place on a large, foil-lined rimmed baking sheet. Bake until cooked through, 20 to 25 min. Transfer meatballs to a saucepan with barbecue sauce and keep warm.
Fill rolls with cheddar and heat in oven until melted, about 5 min. Top with meatballs and sauce, French-fried onions and pickles.
• Use water or cooking spray on your hands to prevent sticking when making meatballs. Or use disposable plastic gloves to roll the meatballs.