Brown veal stock is used in which mother sauce?

Brown veal stock is an essential component of Espagnole sauce, which is one of the five mother sauces in classical French cuisine. Espagnole, or brown sauce, is made by thickening a brown stock with a brown roux and flavoring it with mirepoix, which includes carrots, onions, and celery, along with tomatoes. The use of brown veal stock adds depth and richness to the sauce, which is often used as a base for various demi-glaces and is foundational for many derivative sauces.

In contrast, the other sauces mentioned—Béchamel, Hollandaise, and Tomato—each have distinct bases and do not incorporate brown veal stock. Béchamel is made from a white roux and milk, Hollandaise is an emulsion of egg yolks and butter, and Tomato sauce is derived from tomatoes and typically does not include veal stock, as it is vegetable-based. This distinguishes Espagnole as the sauce that requires brown veal stock, emphasizing its role in creating complex, savory flavors in various dishes.