Often hidden backstreet bars like this - quiet, sophisticated, with tasteful but understated decor - specialize in expensive Scotch whisky or cocktails, so it's nice to find a place like this with a serious Belgian beer menu. Food includes freshly shaved Parmesan, pork rillettes and shepherd's pie, and prices are a bit higher than average (around Y1200-1500 for a typical bottle of Belgian). Located upstairs in a residential-looking building, the bar can be very hard to find, but that's part of its charm.
Shinjuku-ku, Tsukudocho 1-14, Sun Heights Sakatabashi 203. (walk up Kagurazaka-dori and turn right at Gojuban Chinese steamed bun shop, it's on the right side after about 4 min.) Open 5pm-2am. Closed weekends.