Where was custard believed to have been invented?

Custard is a variety of culinary preparations based on milk or cream cooked with egg yolk to thicken it, and sometimes also flour, corn starch, or gelatin. Depending on the recipe, custard may vary in consistency from a thin pouring sauce 'crème anglaise' to the thick pastry cream 'crème pâtissière' used to fill éclairs.

The most common custards are used in desserts or dessert sauces and typically include sugar and vanilla, however savory custards are also found, e.g. in quiche. Mixtures of milk and eggs thickened by heat have long been part of European cuisine, since at least Ancient Rome (no exact date known), where it is believed to have originated.

Custards baked in pastry (custard tarts) were very popular in the Middle Ages, and are the origin of the English word 'custard': the French term 'croustade' originally referred to the crust of a tart, and is derived from the Italian word 'crostata', and ultimately the Latin 'crustāre'. Examples include 'Crustardes of flessh' and 'Crustade', in the 14th century English collection 'The Forme of Cury'.

These recipes include solid ingredients such as meat, fish, and fruit bound by the custard. Stirred custards cooked in pots are also found under the names 'Creme Boylede' and 'Creme boiled'. In modern times, the name 'custard' is sometimes applied to starch-thickened preparations like blancmange and Bird's Custard powder.