Hollandaise sauce mayonnaise and Béarnaise, the egg does not coagulate as in a custard; rather, the lecithin in the eggs serves as an emulsifier, allowing the mixture of the normally immiscible butter and lemon juice to form a stable emulsion. To make hollandaise sauce, beaten egg yolks are combined with butter, lemon juice, salt, and water, and heated gently while being mixed. Some cooks use a double boiler in order to control the temperature. Some recipes add melted butter to warmed yolks; others call for unmelted butter and the yolks to be heated together; still others combine warm butter and eggs in
French cuisine and Franche-Comté. Amongst savorous specialties accounted in the "Cuisine franc-comtoise" from the Franche-Comté region are Croûte aux morilles, Poulet à la Comtoise, trout, smoked meats and cheeses such as Mont d'Or, Comté and Morbier which are at the palate best eaten hot or cold, the exquisite Coq au vin jaune and the special dessert gâteau de ménage. Charolais beef, poultry from Bresse, sea snail, honey cake, Chaource and Epoisses cheese are specialties of the local cuisine of Burgundy. Dijon mustard is also a specialty of Burgundy cuisine. "Crème de cassis" is a popular liquor made from the blackcurrants. Oil are