Lingue di Procida is a traditional sweet pastry originating from the island of Procida. It's usually made with a combination of puff pastry, egg yolks and whites, milk, sugar, flour, and zest of the islands' sweet lemons. The puff pastry is rolled and small ovals are cut out from it.
They're pierced a few times with a fork, and the edges are brushed with egg whites. A spoonful of lemon cream (consisting of zest, sugar, flour, and egg yolks) is spread on top of the ovals, and another puff pastry oval is placed on top. Once assembled, lingue di Procida are brushed with egg yolks and milk, and sprinkled with sugar before they're baked in the oven until golden.