Quick and Easy Lean Beef Meatball Sandwich

Ingredients

• 6 long rolls
• 500g lean beef mince
• 1/2 cup bread crumbs
• 1/4 cup milk
• 1 egg
• 1/4 onion, diced
• 1 clove garlic, crushed
• 1 tsp salt
• 1/4 tsp black pepper
• 2 tsp Worcestershire sauce
• 1/2 cup tomato passata or pasta sauce
• 1/4 cup grated mozzarella cheese
• 1 handful of fresh basil leaves