Bethesda has 2 really exceptional corner stores - both are metro accessible so while not in DC they’re still pretty easy to get to. First is Hinata carryout - they have floor to ceiling imported Japanese goods and a sushi counter in the back. Solid place to get some frozen dumplings and a little treat. Other spot worth stopping for is Ege Market. It’s a Turkish and Mediterranean corner store with some of the best halva I’ve ever had, plus fresh pastries and Turkish coffee behind the counter.