Butter, Cream, and Egg Yolks in Sauce Making

Sauces, especially French sauces, have a reputation for being overly rich—or at least far from dietetic. This is partly true, especially for traditional sauces and for the sauces based on butter and cream that were popular in the last two decades of the twentieth century. But many cooks have since eliminated these fats from their cooking, replacing them with lighter brothlike sauces held together with vegetable puree or not thickened at all. However, fats, especially emulsified fats such as butter, cream, and egg yolks, unite and bring into focus otherwise disparate flavors and make what would otherwise be just a flavorful liquid into a suave and deeply satisfying sauce. Fats carry flavor and deliver them to our palates like nothing else. The bright side is that very little of these calorie-laden fats is needed. For example, traditional cream soup recipes call for about 1 cup cream for each quart of soup. Many cooks overreact and eliminate the cream altogether, ending up with a pleasant pureed soup. But that soup would have been enhanced enormously with the addition of just ¼ cup cream for each quart, or about 1 tablespoon for each serving.