Soak the rolls in warm water. Peel and finely chop the onion. Knead minced, squeezed out roll, egg and onion. Season with salt and pepper. Form 8 meatballs from the mixture.
Fry in hot fat at medium heat on both sides for about 15 minutes each. For the sauce, mix mustard, honey and crème fraîche. Season with sugar and salt. Wash tarragon, dab dry, chop and stir into the sauce.