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 classical music the twentieth-century, composers took many different paths. Some composers looked backwards to the light, elegant Classical works, with the Neoclassicism of the Russian-French composer Stravinsky. Austro-German composers such as Schoenberg and Berg and used a tortured, dramatic style called Expressionism. The French composer Boulez abandoned the entire tonal (key-centered) tradition of Western music with a style called Serialism. Other composers explored electronic music (Stockhausen); chance-based or random (aleatoric) music and indeterminacy (Cage); and minimalism (Reich, Glass). French classical music French classical music began with the sacred music of the Roman Catholic Church, with written records predating the reign of Charlemagne.