Eggs are mixed with other liquids across a tremendous range of proportions. One tablespoon of cream will enrich a scrambled egg, while one beaten egg will slightly thicken a pint of milk into an eggnog. Just about in the middle of this range—at around 4 parts liquid to 1 part egg, or 1 cup/250 ml to 1 or 2 eggs—are the custards and creams, dishes in which the egg proteins give substantial body to otherwise thin liquids. These terms are often used interchangeably, which obscures a useful distinction