Roll the Meatballs:
In a mixing bowl, combine ground beef and pork, ricotta, egg, cheese, parsley, 1 tsp salt and 1 tsp pepper. Mix well to combine ingredients.
Using your hands, scoop up the mixture and shape into balls about the size of golfballs.
Cook the Meatballs and Sauce:
Heat olive oil in a large sauce pan over medium heat. When oil shimmers, add onion and cook until translucent.
Add meatballs and wine, and cook until wine reduce by half.
Add passata, 1 tsp salt, 1 tsp pepper and bring mixture to slight boil. Reduce heat to low and let cook, uncovered up to 90 minutes.
Turn off heat and let rest with lid on for about 1 hour before serving.