Always eat and drink a block or two away from the main tourist attractions.The difference in price for even a coffee can be considerable.
Eat where you see a crowd of locals. If a restaurant is empty,
full of other tourists, or posts a menu outside in five languages, you
can safely assume the locals know something you do not, so move on.
In most restaurants, the best value meal is the set price
lunch which includes at least two courses, beverage, tax and service
charges.
Pay attention to the daily specials and house specialties. These will be the best dishes the chef has to offer, and will usually consist of seasonally fresh foods.
Don't sit down! Drink and eat while standing at the bar. If you
sit down in a café, you can be charged up to twice as much for
the privilege than if you consume your food and drink on foot. If you
sit at an outside table, the tab could be even more. However, the benefit
of sitting is that you acquire something akin to "squatter's rights"
and can linger at your table for the price of a coffee or a beer for
hours without being bothered, or asked to move.
Try to include a trip to a daily market. Not only will you have
a visual banquet of the freshest seasonal foods available, but you can
pick up the fixings for a Cheap Eat picnic lunch or supper to enjoy
at a local park, or discretely in your hotel room.
If at all possible, avoid eating breakfast at your hotel. Arrange
when you reserve to have this inflated cost removed from your total
bill, and instead join the locals standing at the corner café
and save enough money to have a really nice lunch or dinner.
Stay within the limits of the kitchen. Don't expect heel-clicking service and gourmet food in a lousy cafe, and don't go to a formal restaurant and order only a salad.