You can't go to Lisbon and not try pastel de nata and this was probably the best place we found to get your mitts on the delicious egg pastries. Grab a couple with a cup of coffee. Happy days.
In the very touristic Graça area, there is this heaven place, hidden from tourists. This café belongs to the theater da Garagem. It has an amazing view, the atmosphere is peaceful and with a lot of light. They don't have wifi if you plan to work there though..