Demi-glace warm. At this point, the espagnole is prepared, and when it is finished, the brown stock is added in equal portions to the espagnole. Demi-glace keeps very well, about six months refrigerated or almost indefinitely frozen. Due to the considerable effort involved in making the traditional demi-glace, chefs commonly substitute a simple "jus lié" of veal stock or to create a simulated version, which the American cookbook author Julia Child referred to as a "semi-demi-glace"(i.e. sans espagnole sauce). However, even today, many chefs who prepare French "haute cuisine" use a demi-glace prepared in their own kitchen. Concentrates and mixes, mostly
French cuisine Louis XV. This recipe is still popular today, as are other recipes from Queen Marie Leszczyńska like consommé à la Reine and filet d'aloyau braisé à la royale. Queen Marie is also credited with introducing lentilles to the French diet. The French Revolution was integral to the expansion of French cuisine, because it abolished the guild system. This meant anyone could now produce and sell any culinary item he wished. Bread was a significant food source among peasants and the working class in the late 18th century, with many of the nation’s people being dependent on it. In French provinces,