Vadas, or medu vadas, I like a lot. They look and taste like deep fried doughnuts, but they're savory. Like idlis, vadas make for a fairly nutritional breakfast, if you can see past the fact that they're deep-fried. The dough is made with ground up lentils flavored with curry leaves and chilies, and you dip bites of vada into a lentil soup called sambar. All those lentils add up to some decent protein.
If you’re me, however, you dip hunks of vada in chutney, because I just can't get enough chutney.
I've read that a "vada" can be any kind of savory fried snack or fritter, so I'm not sure if the doughnut variety is specific to Chennai or if I simply haven’t encountered other vadas yet.