01 - Combine breadcrumbs and milk in a large bowl. Allow the mixture to soak for 2 minutes until the breadcrumbs absorb the liquid.
02 - Add ground beef, egg, Parmesan cheese, minced garlic, chopped parsley, salt, and pepper to the bowl. Mix gently with your hands until just combined—avoid overmixing to keep the meatballs tender.
03 - Form the mixture into 16 equal-sized balls, rolling them lightly between your palms. Do not pack them too tightly.
04 - Heat 1 tablespoon olive oil in a large skillet over medium heat. Add meatballs in batches, cooking for about 5–6 minutes total until browned on all sides. Remove from the skillet and set aside—they do not need to be fully cooked at this stage.
05 - In the same skillet, add the remaining tablespoon of olive oil. Sauté the finely chopped onion for 3–4 minutes until soft and translucent.
06 - Stir in the minced garlic and cook for 1 minute until fragrant, being careful not to let it brown.
07 - Pour in the crushed tomatoes, then add oregano, basil, red pepper flakes, sugar, salt, and pepper. Stir well and let the sauce simmer for 5 minutes to allow the flavors to meld.
08 - Return the browned meatballs to the sauce, cover the skillet, and reduce heat to low. Simmer for 20–25 minutes, turning the meatballs once halfway through, until they are cooked through and the sauce has thickened.
09 - Serve hot over cooked spaghetti, topped with fresh basil leaves and extra grated Parmesan. Alternatively, enjoy with crusty bread for dipping.