Preheat your oven to 350°F (175°C). In a large bowl, combine the egg, finely chopped parsley, tomato paste, oregano, salt, pepper, minced garlic, and a splash of water. Mix well before adding the ground beef and pork along with bread crumbs and grated Parmesan cheese. Gently fold the mixture with your hands until just combined, avoiding overmixing for tender meatballs. Form into 1-inch balls and place them on a baking sheet lined with parchment paper.

Once your oven is preheated, bake the meatballs for 20 minutes until they develop a golden-brown exterior while remaining juicy inside. After 20 minutes, check their internal temperature; they should reach at least 165°F (74°C).

In a large skillet, melt 2 tablespoons of butter over medium heat. Add the finely chopped onion and sauté for about 5 minutes until soft and translucent. Stir in minced garlic and cook for an additional minute until fragrant. Pour in the marinara sauce and sprinkle in a teaspoon of sugar. Allow the sauce to simmer gently for 5 minutes.

Gradually stir in ½ cup of heavy cream after the sauce has simmered. Continue to simmer for another 2-3 minutes.

Cook the spaghetti according to package instructions in a large pot of salted boiling water for about 8-10 minutes for al dente. Reserve about half a cup of pasta water before draining.

Add the drained spaghetti into the skillet with the creamy sauce. Toss gently to coat the pasta evenly. If the sauce seems too thick, add a splash of reserved pasta water.

Transfer your Creamy Spaghetti and Meatballs to serving plates or a large pasta dish. Sprinkle with extra grated Parmesan cheese and parsley.