One of the many pans I covet is the small, fish-shaped mould used to make taiyaki (Japanese pancakes). These Japanese (or Korean) metal moulds are made of two parts connected by a hinge. The mould is heated and a loose, pancake-like batter is poured in. A filling is added, more batter is poured on top and the top of the mould is folded down to enclose it. After the batter cooks on one side, the mould is flipped over to brown the other side. I've purchased these pancakes from mobile vendors in Korea, but in Japan - which seems to eschew street food - I've bought them in department stores or from small stalls that specialise in them.
While the filling of taiyaki is usually sweet (I especially love the ones filled with mashed azuki beans, although I've also seen them filled with custard), some shops also sell savoury versions. The exterior of the fish should be slightly crisp, giving way to softly cooked batter and the hot filling. While the exterior is usually plain, shops are now making them tinted green (from green tea) or brown (from cocoa).