Preheat oven to 200°C (400°F). Line a baking sheet with parchment paper. In large bowl, use hands to mix together ground meats, eggs, milk, breadcrumbs, Parmesan, parsley, onion, garlic, salt, pepper and nutmeg. Cover and chill about 10 min. for mixture to firm up.
Using 1/3 cup (75 mL) measure, fill to rim with meat mixture. Unmold and roll into ball. Make 16 meatballs.
Heat olive oil in large non-stick skillet on medium heat. Working in batches, brown meatballs on all sides, 3 to 5 min. Transfer to prepared baking sheet. Bake 15 to 18 min. until cooked through and internal temperature reaches 74˚C (165˚F).
To keep meatballs warm, add a thin layer of tomato sauce into the bottom of a slow cooker before adding cooked meatballs. Cover and set on WARM setting for a help-yourself appetizer.
Substitute ground turkey, chicken or lamb.