Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper. In a large bowl, combine the egg, parsley, tomato paste, oregano, salt, pepper, water, and 5 minced garlic cloves. Fold in the ground beef, ground pork, breadcrumbs, and cheese. Roll into golf ball-sized meatballs and place on the baking sheet. Bake for 20 minutes, turning halfway through.

While the meatballs bake, heat a skillet over medium heat and melt the butter. Add the chopped onion and sauté for about 5 minutes until soft. Stir in the remaining 5 minced garlic cloves and cook for another minute until fragrant. Pour in the marinara sauce and bring to a gentle simmer. Stir in the sugar, garlic powder, and paprika.

Gradually add the heavy cream and mix well. Simmer for 2-3 minutes until the sauce thickens slightly and coats the spoon. This creamy sauce pairs perfectly with your baked meatballs.

In a large pot, bring salted water to a boil. Add spaghetti and cook until al dente (about 8-10 minutes). Reserve a cup of pasta water, drain spaghetti, and rinse with cold water.

Return drained spaghetti to the pot and add the creamy marinara sauce, tossing for about 5 minutes. Mix in the baked meatballs and serve hot, topped with extra Parmigiano-Reggiano cheese.