1. Fruit-based, in the form of a coulis made from sweetened or unsweetened fruit puree. Coulis is sometimes thickened with starch or other thickeners such as agar or fruit pectin. Liqueur can be added to augment the flavor. See starch.
2. Custard-based, such as crème anglaise, often considered the queen of dessert sauces. Crème anglaise is a pourable stirred custard made from egg yolks, sugar, milk, and often cream, which may be flavored in many different ways, either during cooking or before serving. See custard. Whole vanilla beans are a common and traditional flavoring element, but whole, fragrant spices such as cinnamon, cloves, and star anise, and herbs such as thyme, tarragon, and rosemary, are often used to infuse the sauce with a complex flavor and then removed once the desired intensity of flavor has been achieved. See vanilla. Crushed coffee beans and whole tea leaves are other flavor enhancers.
3. Sabayon (zabaglione or zabaione, believed to date from the sixteenth century), an emulsified sauce made from a mixture of eggs, sugar, and a sweet wine (traditionally Marsala), dry wine, Champagne, or spirits, including eau de vie. See zabaglione. The mixture is heated over a bain-marie (a simmering water bath upon which a nonreactive bowl is placed) and whipped until thick and foamy. It is served warm or cold.
4. Caramel-based, with or without the addition of a dairy enrichment such as cream or butter. See stages of sugar syrup.
5. Chocolate-based, using cream or milk, or both, and sometimes butter, depending on the desired thickness, and varied according to the viscosity of the chocolate when melted; white, milk, or dark chocolate may be used as the basis of the sauce.
6. Flavoring-based, such as coffee, tea, wine, and liqueur, with alcohol enhancements and various sweeteners other than refined sugar, including maple syrup and agave syrup. See maple syrup and tea.
7. Semi-solid sauces, such as hard sauce, a mixture of butter, sugar, and usually rum or brandy. Such thick sauces resemble an icing that melts when ladled over a warm dessert. See icing. They originated in England and have been used in the United States since the late nineteenth century as an accompaniment to steamed and bread puddings.