Bread sauce

A bread sauce is a warm or cold sauce which is thickened with bread.

The sole survivor of the medieval bread-thickened sauces, the traditional British bread sauce is made with milk, butter or cream, and bread crumbs, flavoured with onion, salt, cloves, mace, pepper, and bay leaf, with the fat from roasting often added too. It typically accompanies domestic fowl such as turkey or chicken. The use of slightly stale bread is optimal, making it an economical way of using up leftover bread. The sauce is easy to make and uses readily available ingredients.

The basic recipe calls for milk and onion with breadcrumbs and butter added as thickeners.

Turkish cuisine also features a cold sauce made from breadcrumbs mixed with pounded walnuts or hazelnuts and served with chick pea salads and, most famously, with chicken or duck as Circassian chicken.

Bread sauce can be traced back to at least medieval times, when cooks used bread as a thickening agent for sauces. The utilisation of bread in this way probably comes from cooks wanting to use up their stale bread who discovered that it could be incorporated within sauces to make them thicker.

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Wikipedia