For the meatballs:
Preheat oven to 425 degrees F.
In a bowl, mix together the butter, onion, milk, eggs, bread crumbs, black pepper, nutmeg, allspice, salt, cayenne, ground chuck, and ground pork.
Form the mixture into meatballs and place them on a baking sheet.
Bake the meatballs in the preheated oven for about 20-25 minutes or until browned.
For the sauce:
In a saucepan, melt butter over medium heat.
Stir in the flour and cook for a few minutes until it forms a paste.
Gradually whisk in the beef broth and cook until thickened.
Add the heavy cream, sugar, Worcestershire sauce, salt, and pepper. Cook until heated through.
Serve the meatballs with the sauce.
*Note: Adjust salt in both meatballs and sauce to taste.