When I was in DC I went to the Good Stuff Eatery, brainchild of Spike (Top Chef fame) and Cathy Mendelsohn. I had THE BEST shake. It was toasted marshmallow and it was delicious. When I was pregnant one of the things I craved was marshmallows. I ate them all time time. It's a good thing I didn't live anywhere near this place or I would have gained a thousand pounds. My burger was tasty too. If you're in DC in the Capitol Hill area, you have to check this place out. It can get crowded on a weekday lunch hour but it was worth the wait for a table. You can take your food to go too.
GET THE SHAKE...IT'S TOASTED!