Tocino de cielo is a traditional dessert that originated in the monasteries of Jerez de la Frontera and Montilla-Moriles in the 19th century. The dessert is made with water, sugar, and eggs, while the caramel part is made with only sugar and water.
The beaten eggs are combined with warm sugar syrup, then poured into the caramel-coated molds and baked until the custard has set. When done, the dessert is chilled in the refrigerator for a few hours or overnight. Tocino de cielo is served turned upside down, with all of the caramel sauce drizzling out underneath it, so the dish should be deep enough to collect it.