1/4 cup chopped yellow onion
1 can (15-oz) diced tomatoes, drained; juice saved
1 can (8-oz) tomato sauce
2 tbsp tomato paste
1 tsp dried Italian seasoning
1 lb ground chicken (read label; no ground skin)
1/2 cup whole-grain bread crumbs (approx 1 slice, crumbled)
1 egg white lightly beaten
3 tbsp finely chopped fresh parsley
2 cloves garlic, minced
1/4 tsp salt
couple dashes of black pepper
4 small hard sub rolls
2 tbsp grated Parmesan cheese
Combine the onion, tomatoes, 1/2 cup of the tomato juice, tomato sauce, tomato paste, and Italian seasoning in the slow cooker or crockpot. Cover and cook on low setting for approximately 4 hours until the onion is soft.
During the last 30 minutes of the above cooking time, prepare the meatballs by combining the chicken, bread crumbs, egg white, parsley, garlic, salt and pepper together in a medium bowl. Wet hands and form the mixture into 12 to 16 equal-sized meatballs. Spray a medium skillet with nonstick cooking spray and heat over medium heat. When skillet is hot, add the meatballs and cook approximately 10 minutes until browned all over and cooked thoroughly.
To make sandwiches: Place 3 to 4 meatballs on the bottom of each sub roll. Evenly divide the sauce over each of the 4 sandwiches. Sprinkle the cheese over the sauce, top with other part of the roll and serve.