This will get you started on some in addition to what has already been mentioned.
Maize (corn):
On the cob: boiled or roasted
Off the cob: boiled, creamed, fried, fritters, chowder, custard, mixed with equal part lima beans (succotash)
Dried and ground: cornbread, muffins, hoecakes, pancakes, as a coating for fried foods like fried catfish or okra or tomatoes, as a cereal (corn meal mush)
Tomatoes:
Stuffed and baked, stewed, stewed with bread (breaded tomatoes), tomato and okra gumbs, soups, sauces, sliced and broiled, picked and sliced green then dredged in flour or cornmeal or batter and fried (fried green tomatoes), or just eaten raw - alone or added to salads, sandwiches, etc.
Potatoes:
Baked, boiled, mashed, fried, hash browns, soup, chowder, potato salad
Sweet potatoes:
Baked, mashed, fried, quick breads, muffins, pies
Pumpkin:
Quick breads, muffins, pies, soup
This doesn't even get into uses for other native summer and winter squashes, beans, etc.