The classic Thanksgiving menu of turkey, cranberries, pumpkin pie, and root vegetables is based on New England fall harvests. In the 19th century, as the holiday spread across the country, local cooks modified the menu both by choice ("this is what we like to eat") and by necessity ("this is what we have to eat"). Today, many Americans delight in giving regional produce, recipes and seasonings a place on the Thanksgiving table. In New Mexico, chiles and other southwestern flavors are used in stuffing, while on the Chesapeake Bay, the local favorite, crab, often shows up as a holiday appetizer or as an ingredient in dressing. In Minnesota, the turkey might be stuffed with wild rice, and in Washington State, locally grown hazelnuts are featured in stuffing and desserts. In Indiana, persimmon puddings are a favorite Thanksgiving dessert, and in Key West, key lime pie joins pumpkin pie on the holiday table. Some specialties have even become ubiquitous regional additions to local Thanksgiving menus; in Baltimore, for instance, it is common to find sauerkraut alongside the Thanksgiving turkey.
Most of these regional variations have remained largely a local phenomenon, a means of connecting with local harvests and specialty foods. However this is not true of influential southern Thanksgiving trends that had a tremendous impact on the 20th-century Thanksgiving menu.
Corn, sweet potatoes, and pork form the backbone of traditional southern home cooking, and these staple foods provided the main ingredients in southern Thanksgiving additions like ham, sweet potato casseroles, pies and puddings, and corn bread dressing. Other popular southern contributions include ambrosia (a layered fruit salad traditionally made with citrus fruits and coconut; some more recent recipes use mini-marshmallows and canned fruits), biscuits, a host of vegetable casseroles, and even macaroni and cheese. Unlike the traditional New England menu, with its mince, apple and pumpkin pie dessert course, southerners added a range and selection of desserts unknown in northern dining rooms, including regional cakes, pies, puddings, and numerous cobblers. Many of these Thanksgiving menu additions spread across the country with relocating southerners. Southern cookbooks (of which there are hundreds) and magazines also helped popularize many of these dishes in places far beyond their southern roots. Some, like sweet potato casserole, pecan pie, and corn bread dressing, have become as expected on the Thanksgiving table as turkey and cranberry sauce.