Cut the saithe fillets into serving pieces and sprinkle with salt and pepper. Dredge the pieces with flour and fry in browned butter on both sides.Clean the onion and cut into wedges.Clean the leek and cut into rings. Clean and finely chop the garlic. Stew the onion, leek and garlic over moderate heat in butter or olive oil. Sprinkle with salt, pepper and plenty of fresh chives.Serve with boiled potatoes cut into slices and fried until lightly browned.