Sauce Foyot (Valois)
The science
A spoonful of glace de viande folds the deep, gelatinous, roasted-meat concentrate of the brown-sauce world into the bright butter emulsion of Béarnaise — a rare and elegant crossover that marries the two great sauce families. The glaze deepens color and adds a savory, meaty undertone without breaking the emulsion, since it is added in small quantity and gently.
Flavor profile
Béarnaise enriched with glace de viande (meat glaze).
Culinary uses
Grilled and roasted red meats, tournedos, where a meatier Béarnaise is wanted.
Reference notes
Parent: Béarnaise → Hollandaise. Crossover ingredient: glace de viande (from the Espagnole family) — flag as a teaching example of inter-family linkage.