Place the oven rack about 6 to 8 inches, underneath the broiler. Preheat the broiler and line a rimmed baking sheet with aluminum foil.
Cook pasta according to package directions, in salted water. Drain; return the pasta to the pot.
While the pasta is cooking, prepare the meatballs.
In a large bowl, whisk together the egg, 2 tablespoons of water, and season with salt and pepper to taste. Stir in the garlic, parsley, breadcrumbs, and Parmesan. Let this mixture sit for 2 minutes.
Chop 1 cup of the spinach. Add the chopped spinach, beef, sausage, to the breadcrumb mixture; mix to combine.
When the meat mixture is well combined, use about two tablespoons per meatball to form 1 ½-inch balls and place on the prepared baking sheet; about 20 meatballs. Broil the meatballs, until cooked through, about 8 to 10 minutes.
Pour the tomato sauce into the pot with the pasta and toss to combine.
Stir in 1 cup of the mozzarella and about ¼ cup of the ricotta cheese, until it starts to melt. Pour the mixture into a large casserole dish and gently toss with spinach and meatballs. Sprinkle with the remaining mozzarella cheese and dollop with the remaining ricotta cheese.
Broil until the cheese is golden brown; about 3 to 5 minutes.
I found it best to work the meatball mixture with your hands, like you would a meatloaf. If you use your hands, make sure you don't overwork the meat, which can lead to dry, dense meatballs.
Did you try this recipe? Tell us what you think!Give this recipe a star rating, leave a comment below and share pictures of your food with us on Instagram, Facebook or Twitter! We can't wait to see them! Don't forget to mention @TheMountainKitchen or tag #TheMountainKitchen!
Thanks for visiting TheMountainKitchen.com We hope you like this recipe. Please share your thoughts about this recipe with us!