Star anise and fennel add an Asian twist to salt-cured salmon, a Scandinavian classic.
Combine sugar, salt, star anise, and peppercorns in a spice grinder or mortar and pestle and grind until spices are well crushed. Rub fish well with the mixture.
Arrange chopped fennel leaves, lemon slices, and any leftover seasonings in a glass baking dish large enough to hold the fish flat. Sprinkle flesh side of fish with vodka and lay in dish, skin side up.
Cover fish with plastic wrap and place a wooden cutting board on top. Weight with cans. Cure in refrigerator for 2 to 3 days. Fish should look opaque when done.
Remove fish from baking dish and brush off seasonings. Serve immediately, or rewrap and refrigerate for 1 to 2 days.
To serve, slice very thinly on an angle down to skin. To assemble hors d'oeuvres, top each cracker with a slice of gravlax, a slice of fennel, some fennel leaves, and a sprinkling of sesame seeds.