A doughnut in Petaluma is a fried dough food that is prepared in various forms as a sweet snack that can be homemade or purchased in bakeries, supermarkets, food stalls, and franchised specialty outlets. They are usually sweet, deep-fried from a flour dough, and shaped in rings and flattened spheres, ear shapes, twists and other forms, that sometimes contain fillings. Other types of dough such as potato can also be used as well as other batters, and various toppings and flavorings are used for different types. A doughnut may be filled with jam or jelly, cream, custard, or other sweet fillings. Doughnut varieties are also divided into cake and risen type doughnuts.