Start by preparing the meatballs. Mix 500 grams of minced meat, 1 finely chopped onion, 2 cloves of minced garlic, 1 beaten egg, 50 grams of breadcrumbs, and salt to taste. Form into small balls and set aside.
Heat 2 tablespoons of oil in a pan over medium heat. Add the meatballs and cook until browned on all sides. Remove from the pan and set aside.
In the same pan, add 1 chopped onion, 2 cloves of minced garlic, and sauté until golden brown. Add 500 grams of crushed tomatoes, 1 teaspoon of sugar, salt to taste, and simmer for 20 minutes.
Add the meatballs back into the sauce and cook for another 10 minutes.
Meanwhile, cook 200 grams of spaghetti in a large pot of boiling salted water until al dente. Drain and set aside.
Serve the meatballs and sauce over the cooked spaghetti. Garnish with freshly grated Parmesan cheese and fresh basil leaves.