My husband likes to eat healthy. I talked about it a little when I made mackerel in my Holy Mackerel! post. Aji is a type of mackerel--Spanish mackerel, and mirin-boshi means it's saturated in mirin--sweet cooking sake. This is my husband's idea of a great meal. All I really have to cook is rice--and then I send him outside to grill the fish! I bought this package at Marukai Market. You can most likely find something like it at any Asian grocery store. What you're looking for is Aji (that's Spanish mackerel) Mirin-Boshi.