How to Make It
Prepare the Meatballs: Preheat oven to 400°F. Coat a 24-cup miniature muffin pan with cooking spray. Place sausage in a large bowl, and let stand at room temperature 15 minutes. Gently stir in egg, apple, onion, Parmesan, sage, and 1/4 cup of the breadcrumbs. (Mixture should be well combined but not overworked.) Using gloves or hands dipped in ice water, gently shape sausage mixture into 24 (1 1/2-inch) balls. Coat balls lightly in remaining 1/4 cup breadcrumbs; place 1 ball in each prepared muffin cup.
Bake in preheated oven until browned on the bottom and beginning to sizzle around the edges, about 10 minutes. Remove from oven, and, using tip of a knife, turn Meatballs over. Return to oven, and bake until cooked through and well browned, about 10 minutes. Remove from oven, and let stand 5 minutes.
Meanwhile, prepare the Dipping Sauce: Stir together apple butter and mustard in a small bowl. Place Meatballs on a serving platter, and, if desired, garnish with parsley. Serve warm with Dipping Sauce