8. Sauces for food became popular during the medieval period
At the beginning of the medieval period, the sauce with which food was served was based on milk, or wine, or butter, or simply the juices which emerged as part of the cooking process. Because bread was so important to the overall caloric intake, flour could not be wasted to prepare sauces and gravies, except for on the tables of the very rich. Nor were there a variety of spices available to flavor them, until later in the period. Throughout the medieval period, the preparation of sauces evolved, and the art of cookery evolved with it, both in the kitchens of the wealthy and on the hearths of the less well-to-do. The earliest sauces were coarse, and would not be recognized as sauces today.
One such was porridge, made from oats, which could be served in a variety of thicknesses, including a very thin broth known as gruel. It was consumed separately or as a sauce with bread or vegetables. The earliest known beers were simply fermented gruel, though by the medieval period the preparation of beer had become more sophisticated and refined. Sauces, as were most foods, were prepared over an open fire, which made the cooking of complex mixtures difficult, as temperature control was iffy at best, and pots and pans were heavy affairs, difficult to manipulate over the fire.