This is the mackerel-focused restaurant at Wisma Atria's Japan Food Town (435 Orchard Road #04-50, 6262-3453). They serve it in a number of different ways, including sushi and ramen forms, among others. I went with the traditional grilled version above, and it turned out to be huge. Actually, it was only half of the fish, but it had little morsels of tasty fat tucked underneath that crispy skin. I'd be interested in trying the hitsumabushi version that I saw on the menu once they make it available.