This paradise of Japanese-style sandos hides in a strip mall. A no-frills walk-up counter serves nearly 60 varieties, each cut into two crustless halves, neatly wrapped in a cellophane triangle. The choices (from BLT to okonomiyaki to rum raisin custard, all on the fluffiest bread) can boggle the mind. But know this: The top row of the display cases contains Tres’s top sellers. The pork katsu and anything involving the dainty egg salad offer a great starting point.