1. In a large bowl, combine beef and pork using your hands. Mince 1/2 clove garlic and add to meat mixture along with the eggs, cheese, and parsley; season with salt and pepper. Continue mixing with your hand until well combined. Add bread crumbs and mix well. Add water, 1 cup at a time, and continue mixing until mixture is quite moist.

2. Shape mixture into 2 1/2-to-3-inch balls. Heat oil in a large skillet over medium-high heat. Smash remaining clove of garlic with the back of a knife and add to skillet. Cook until lightly browned and fragrant, 1 to 2 minutes; remove with a slotted spoon and discard. Working in batches, add meatballs to skillet. Cook until browned and cooked through, turning, about 10 minutes. Drain on paper towels and serve immediately.

3. Meanwhile, bring marinara sauce to a boil in a large nonreactive saucepan. Reduce heat to a simmer and add meatball. Let meatballs cook in sauce about 20 minutes; serve immediately with pasta, if desired.