In a large mixing bowl, combine the ground beef, Italian seasoned bread crumbs, sea salt, black pepper, flour, and the egg. Mix everything together until just combined; avoid overmixing to keep the meatballs tender.
With your hands, roll the meat mixture into balls about the size of a golf ball. You should get around 12-15 meatballs depending on the size you choose.
Heat the olive oil in a skillet over medium heat. Once hot, add the meatballs and cook until they are browned on all sides, about 5-7 minutes. They do not need to be fully cooked at this stage, as they will finish cooking in the sauce.
Once the meatballs are browned, carefully pour the pasta sauce over them in the skillet. Cover and let simmer for 20-25 minutes on low heat, allowing the meatballs to absorb the flavors of the sauce.
While the meatballs are simmering, bring a large pot of salted water to a boil. Add the spaghetti and cook according to package instructions until al dente. Reserve a cup of pasta water, then drain the spaghetti.
Add the cooked spaghetti to the skillet with the meatballs and sauce. Toss everything together, adding a little reserved pasta water if needed to loosen the sauce. Serve hot, topped with grated Parmesan cheese!
