In a medium bowl combine ground beef, breadcrumbs, grated Parmesan, milk, egg yolk, minced parsley, garlic powder, 1/4 tsp salt and 1/4 tsp black pepper. Gently mix with your hands or a fork until just combined; avoid overworking so meatballs stay tender.

Form

Dampen your hands slightly and roll the mixture into 6 small child-size meatballs (about 1 inch / 25 mm each). Place them on a plate or tray.

Cook

Heat 1 teaspoon olive oil in a small nonstick skillet over medium heat. Add the meatballs and cook, turning gently, until browned on all sides and cooked through, about 6–8 minutes total depending on size. Remove to a plate and set aside. Alternatively, you can bake them at 190°C / 375°F for 12–15 minutes.

Sauce

Sauté aromatics

In the same skillet, add 1 teaspoon olive oil if needed and set heat to medium-low. Add the finely chopped onion and sauté until soft and translucent, about 3–4 minutes. Add the minced garlic and cook 20–30 seconds until fragrant.

Simmer sauce

Pour in 1 cup tomato passata or crushed tomatoes. Stir in dried oregano, dried basil, 1/2 teaspoon salt and 1/4 teaspoon black pepper. Bring to a gentle simmer. If the sauce is very thick, add up to 2 tablespoons water to reach a child-friendly consistency. Return the cooked meatballs to the skillet, spooning sauce over them. Simmer gently for 5–7 minutes so flavors meld and meatballs finish cooking. Taste and adjust seasoning (add a pinch more salt if needed).

Pasta & Finish

Cook spaghetti

Bring 1 liter (about 4 cups) of water to a rolling boil in a small pot. Add 1 teaspoon salt. Add 2 ounces (about a small child portion) of spaghetti and cook until al dente, about 7–8 minutes (or according to package directions for a firmer bite). Stir occasionally to prevent sticking.

Drain and toss

Reserve 1 tablespoon of pasta cooking water, then drain the spaghetti. Return pasta to the pot off the heat, add 1 teaspoon butter (optional) and 1 tablespoon reserved pasta water if needed; toss gently to coat.

Assemble

Place the child portion of spaghetti in a small bowl. Spoon 2–3 meatballs on top and ladle 1/4–1/3 cup of the warm tomato-meatball sauce over the pasta. Sprinkle 1 teaspoon grated Parmesan on top and garnish with a small basil leaf if using.

Serve

Serve warm, checking temperature for a child. Cut meatballs into halves or quarters if serving to very young children. Leftovers can be refrigerated for up to 2 days.