Time Out Market in Lisbon was great for lunch. We tried food from at least half a dozen places in the market.
We stayed down the street from Manteigara and got egg tarts there several times. They were definitely the best of all we tried except the place where they originated in Belem. The egg tarts in Belem were one of the best desserts I've eaten anywhere. We had great sea food in the Belem neighborhood as well down the road from the egg tart place.
Didn't try any fancy places to eat because we were traveling with a 9 month old, but all the food in Lisbon was great. Cervejaria Ramiro is one of the places I remember enjoying.