Place half the fish, skin side down, in a deep glass dish. Spread dill over fish. Sprinkle dry ingredients over dill. Top with the other half of the fish, skin side up.
Cover with foil and weight with a board and a five pound weight. Refrigerate for 48-72 hours, turning the salmon and basting every 12 hours with accumulated juices.
To serve, remove the fish from marinade, scrape away dill and spices, and pat dry. Slice salmon thinly on the diagonal and serve on small plates or squares of black bread. Garnish with lemon wedges and black pepper and accompany with Dill Mustard Sauce.
Source: The Silver Palate Restaurant, NYC