Spinach:
1. Heat olive oil in a skillet over medium heat. Add baby spinach and toss until coated. Let it wilt for a few minutes.
2. Add finely chopped garlic to the skillet and sauté for another minute or two until it smells fragrant.
3. Remove spinach from the skillet, chop it into small pieces, and set aside to cool.

Meatballs:
1. Preheat oven to 350°F (175°C).
2. In a large bowl, mix together ground beef, ground pork, bread crumbs, eggs, milk, chopped garlic, Parmesan cheese, salt, pepper, and 1/2 of the cooled spinach/garlic mixture.
3. Shape in to balls.
4. Place on a sheet tray lineed with baking paper.
5. Top raw meatballs with spinach, mozzarella cheese, & a drizzle of olive oil.
6. Cook for 20 to 30 minutes.

Sauce
1. Warm up the marinara sauce on the stove, or in the microwave.
2. Serve a spoonfull of sauce on each plate.
3. Place several meatballs on top of the sauce