There are many pay by the kilo restaurants in Bahia. You serve your own food from a buffet style desk and then they weigh your plate before you eat it. They charge you by the kilo !
I ate at many and the food was tastie. The prices varied but worked out to be fairly cheap. It's a good opportunity to try a whole lot of different North East Brazillian foods.
One of the most famous ones is Cantina da lua.
They often have live music which is nice when you are eating Brazillian food.
Favorite Dish Feijoada with farofa. Very basic but easy on the stomach. Good sustainance for beer drinking packers !