Adding Vegetable Purées

Much of the butter or oil used to prepare these sauces can be replaced with various purées, which contribute flavor without making the sauce excessively rich. Mushroom purée, carrot purée, onion purée (soubise), garlic purée, freshly prepared parsley purée, asparagus purée, artichoke purée, watercress purée, puréed tomatoes, puréed tomatillos, and truffle purée can all be used to finish emulsified sauces (see Chapter 18, “Purées and Purée-Thickened Sauces”).