I've just come back from Portugal and man, these people know how to eat! Most food there was simple, reasonably priced, of good quality, and in big portions. Some highlights:
Francesinha: A grilled sandwich filled with beef, sausage and ham, topped with a fried egg and melted cheese, floating in a beer or Port-based sauce with fries. Great hangover cure or very filling lunch.
Bifana: a roll stuffed with a very generous helping of roast pork, and costs less than a couple of euros.
Petiscos: similar to tapas. Olives, bread, ham, cheese, grilled sausage, etc. This was a petiscos night in my hostel in Lisbon:
Pastel de nata: the famous custard tart. Find a bakery that serves them fresh so the pastry is still crunchy and the filling warm. However it's not the only one and you really can't go wrong with any of the pastries and cakes there (unlike in places like Italy where looks are often deceiving and excessive icing sugar can ruin everything). Everything is as good as it looks.
20+ Portuguese pastries and cakes. Possibly the best thing I ate was a creamy caramel sponge cake, but I can't find the name of it.
In Lisbon I had a meal with soup, fish, wine, and dessert for less than ten euros. You just need to know where to go. Lisbon is famous for cod (bacalhau) and sardines.
Wine is also generally good and cheap. There's port of course, vinho verde (young wine), and regular wine (almost always a blend rather than a single grape variety, but still high quality).
I recommend Portugal to everyone... Except perhaps vegetarians!
In reality there are some good meat-free restaurants these days and I had an excellent veggie burger in a place in Lisbon.
Now it's time to cut down on sugar. It's gonna be hard.
Some other highlights from my travels: everything in Italy (special mention to Turin for excellent savoury food as well as the best gelato and hot chocolate, and Genova was up there too); fried fish and fried aubergines (berenjenas) in Andalucía; and basically everything in Vietnam was cheap and tasty.