Heat the oven to 220 C / 425 F. Set a wire rack over a rimmed baking sheet and lightly coat the rack with cooking spray.

Combine the breadcrumbs and skim milk in a large bowl. Stir and leave to soak for 5 minutes until the crumbs are fully absorbed and paste-like.

Add the ground turkey, ground beef, Parmigiano, egg, minced garlic, parsley, oregano, salt, and pepper to the breadcrumb mixture. Mix with your hands until just combined, do not overwork.

Wet your hands with cold water. Portion the mix into 20 equal balls, roughly 28 g each, rolling each one firmly once between your palms. Place on the prepared rack.

Bake for 18 to 20 minutes until golden on the outside and the internal temperature reads 74 C / 165 F on an instant-read thermometer.

While the meatballs bake, heat the olive oil in a large oven-safe skillet over medium heat. Add the sliced garlic and cook for 60 seconds until pale and fragrant, not browned.

Pour in the passata, add oregano, salt, and red pepper flakes if using. Stir and bring to a gentle simmer. Cook uncovered for 10 minutes, stirring occasionally, until the sauce thickens slightly.

Nestle the baked meatballs into the simmering sauce. Spoon sauce over each meatball and cook together for 5 minutes over medium-low heat so the meatballs absorb the sauce flavor.

Taste the sauce and adjust salt. Serve immediately, or leave covered off the heat for up to 15 minutes before serving.