Pastel de nata (or pastel de Belem) - one of the great pastries of the world. I'm ashamed to admit I'd only had one or two prior to going to Lisbon, and that was from a bakery in Cambridge (which was quite good I should add).
The pastry is an egg custard flavoured with vanilla and cinnamon. It is sweet and soft and best warm (although cold after takeaway is certainly ok), with a crisp but juicy pastry cup. One of the things to do in Lisbon is try them everywhere and see which is your favourite. They originated in the suburb of Belem (15min tram, west part of Lisbon) and naturally people regard those ones to be the best. However it isn't an area that people go to regularly and so it's simply more convenient to find a nice one in the city.
One of the tips online was to only try places that had the words "fabrico proprio" (ie. made on the premises) to ensure the product they sold was homemade and a higher chance of being good.
The local woman who checked me in at my hostel gave me a good selection of food options on my arrival. I think she was happy that for once there was someone at the hostel who wasn't on a tight budget and would be willing to try the best Lisbon had to offer. Her favourite (and my first for Lisbon) pasteis for convenience was at Nata. She did say the best was in Belem (naturally) but this was the local one just around the corner from the hostel (and also one location up near Castelo de São Jorge entrance). I ended up eating about 3 from here over the course of 3 days. Sweet, warm, crispy, delicious.
Having found one that I liked, I wasn't overly adventurous to try others in the area. I did relent once and buy from Casa Brasileira. Although it was fabrico proprio, the nata was disappointing. Sweet but average filling, and the pastry was rock hard bordering on sharp. I learnt my lesson not to be so creative on a limited timeframe.
Belem is certainly worth a daytrip, not just for nata but also the incredible Jeronimo's Monastery and the river walk to see Belem Tower and Monument to the Discoveries. However nata is the name of the game for this post. I had read a blog post that tried many different nata, and rated the one at A Chique De Belem as the best. Naturally I had to try it. It had some kind of certificate of honour, and a few locals were standing at the counter eating their 10am nata. It was good, with a much more burnt custard. The pastry here was softer than previous with a nice bit of chew.
Finally onto the most famous of them all, and the one that gets the most attention. Pasteis de Belem is a place that you have to plan to go to. Friends have waited 30-60mins in line for these. Luckily I arrived so early that the queue was only a few minutes. Shortly after, the hordes of tour buses arrived and unloaded millions of minions. I appreciate they have a system where you queue once, and so when I went back in line to order some more, the cashier saw me (not many Asians around so maybe I was memorable?) and brought me to the front of the line and said "you only queue once" and took my order. Great system. The nata here is gorgeous. The pastry has a thin crisp exterior that holds together well and houses a softer pastry underneath. The custard is sweet, delicious and lovely. They like to serve it with a lather of cinnamon sugar on top (which I honestly prefer not to have) which sets them apart from the others I'd seen. I don't know if it's the hype or the atmosphere, but I left here feeling that these ones were great.
Honestly if you lined up the three from Nata, Chique and Pasteis (without cinnamon) I probably couldn't pick them in a blind taste test (unless they were all very fresh in my mind). They are all good, you won't be disappointed. Pasteis de Belem is the one to get for the reputation and the cute takeaway containers (only when in the area and the queues aren't bad).