Prepare the Meat: Debone the rabbit, then blend the rabbit meat until minced.
Blend Onions: Blend or grate the onions until fine.
Make the Frikadeller Mixture: In a bowl, combine the minced rabbit, egg, blended onions, cream, potato flour, salt, and black pepper. Mix until well combined.
Refrigerate: Let the mixture rest in the refrigerator for 30 minutes.
Form and Fry: Form the mixture into small patties and fry in a pan with oil and butter until golden brown on both sides.