Portuguese-style egg tarts were evolved from 'pastel de nata", a traditional Portuguese custard pastry that consists of custard in a creme-brulee-like consistency caramelized fashion in a puff pastry case. It was created more than 200 years ago by Catholic Sisters at Jeronimos Monastery at Belem in Lisbon.
Casa Pastéis de Belém was the first pastry shop outside of the convent to sell this pastry in 1837, and it is now a popular pastry in every pastry shop around the world owned by Portuguese descendants.
The Portuguese-style egg tarts known in Macau originated from Lord Stow's Café in Coloane, owned by a Briton named Andrew Stow. Stow modified the recipe of pastel de nata using techniques of making English custard tarts.