Pasteis de Belem was founded in 1837. They claim that the recipe for their Pasteis (natas) came directly from Mosteiro de Jeronimos next door, as all convents and monasteries in Portugal were shut down in 1834.
Pateis de Belem has gained worldwide fame for their natas. Lines in excess of one hour are not uncommon. Although it looks tiny from the front, as the bakery counter and store is very small, the restaurant/bakery seats approximately 400 people. One way to avoid the lines is to be seated at a table, and order natas to your heart content.
Although they sell much more than natas, that is the main attraction and I would venture that 99% of the people order the natas.
The natas are a little different. The crust is more crisp, rather than buttery and somewhat flaky like most natas found in the Lisbon area.
The milky custard center has nice char marks that adds a slight bitterness to offset the sweetness of the custard. We went here on two occasions. The first time, the nata was really not that sweet and it was my favorite during the trip. On the second trip, it was much sweeter which made Manteigaria my favorite during the trip.
I did not do an actual side by side taste test, which probably should have been done in hindset. A trip to Pasteis de Belem is a must in order to try the original nata.