Pastéis de Nata, also known as Portuguese custard tarts, are a beloved Portuguese dessert. With the help of a food processor, making the pastry for these tarts becomes a breeze. Start by pulsing flour, salt, and cold butter in the food processor until the mixture resembles coarse crumbs. Add cold water and pulse until the dough comes together. Roll out the dough and use it to line tart molds. For the custard filling, blend milk, sugar, cornstarch, egg yolks, and vanilla extract in the food processor until smooth. Pour the custard into the tart shells and bake until golden and caramelized. The result is a flaky pastry with a creamy, sweet custard filling that will transport you to the streets of Lisbon.