It's a easy as pie and it looks like a cake! This is a variation of oshi-zushi, a form of sushi made in box molds. This one uses fresh (raw) sashimi salmon, but can be adjusted for smoked salmon or cooked flaked salmon, just by reducing the seasoning in the rice. Try fresh dill weed instead of perilla leaves. Green and pink peppercorns make great garnish for the holidays too.