Just about everyone who has ever sat down to a Thanksgiving dinner knows about sweet potatoes. They're the orange stuff with the marshmallow topping in the casserole dish that makes at least two or three people in every family just a tiny bit suspicious.

It's a new day, however, for one of the most distinctively colored vegetables in the food chain. "It's not just brown sugar, cinnamon and marshmallow anymore," Sue Johnson-Langdon, executive director of the North Carolina Sweet Potato Commission, said. North Carolina and several other southern states are major producers of sweet potatoes, which have become quite the trendy tuber in the last several years.

Inventive new dishes like sweet potato French fries are one reason that the public perception of the sweet potato is expanding beyond the "holiday dinner" niche. Another important factor, however, is that sweet potatoes are good for you.

"They are an excellent source of Vitamin A and fiber," said Joanna Wilkins, a registered dietitian who lives in Payson and teaches occasional cooking classes at Macey's Little Theater in Provo. "They are also a good source of Vitamin C."

Johnson-Langdon said that there's more fiber in one sweet potato than in a bowl of oatmeal. Sweet potatoes are also a significant source of healthy carbohydrates. Johnson-Langdon said that the slow-digesting "carbs" in sweet potatoes won't elevate your blood pressure, making them preferable to many other high-carb foods.

Unlike some other things that are good for you, however, sweet potatoes taste, well, sweet. That's a drawback for some people: Johnson-Langdon said that a sweet potato, unlike a normal potato, is less apt to take on the flavor of whatever you serve it with.

If you crave that distinctive flavor, on the other hand, then the sweet potato is an excellent main ingredient for a variety of recipes. Johnson-Langdon said that sweet potato soups, risottos and gnocchis are becoming popular.

Wilkins is a fan of the traditional sweet potato casserole, but said that she also likes to cut up sweet potatoes, roast them with other vegetables and serve the mixture with fresh avocado and feta cheese in a whole-wheat tortilla. "They're so delicious when they're roasted," Wilkins said

Sweet potatoes were first cultivated in South America about 5,000 years ago, although they also have a long history in the Cook Islands and other Pacific Island regions. The largest producer of sweet potatoes today is China. North Carolina is the leader in the United States, followed by California, Louisiana and Mississippi.

The growing season, Johnson-Langdon said, is about 120 days in the United States, but fresh sweet potatoes are available year round. Orange-fleshed sweet potatoes are often sold as "yams" in the United States -- to distinguish them from less popular lighter-hued varieties -- but they are actually quite distinct from botanical yams, which are indigenous to Africa and Asia and can weigh up to 150 pounds. Sweet potatoes sold as yams in the United States must also be labeled sweet potatoes.

Though sweet potatoes with brown skin and orange flesh are probably the variety most widely consumed in the United States, the color of the skin can range between red, purple, brown and white, while the flesh can be yellow, purple or orange.

You can grow your own sweet potatoes in Utah, though Wilkins said that she typically buys hers at the grocery store. Wilkins likes to look for large, rounded sweet potatoes, rather than the longer, skinnier ones. Johnson-Langdon said to avoid any individual sweet potatoes that are discolored or have soft, sunken patches. "Other than that," she said, "you're good to go."

Twice-Baked Sweet Potatoes

Serves 12

• 6 sweet potatoes, baked, slightly cooled

• ½ cup butter or margarine, melted

• ¹⁄₃ cup apple juice

• 2 tablespoons brown sugar

• ½ teaspoon ground ginger

• 1 cup mini marshmallows

• ¹⁄₃ cup flaked coconut

• 1 tablespoon butter or margarine, melted

Preheat oven to 350 degrees. Cut potatoes in half lengthwise. Scoop out filling, leaving about 1/8-inch thick shells. Mash potatoes in a medium bowl with butter, apple juice, sugar and ginger. Whip until fluffy. Spoon into shells. Mix marshmallows, coconut and 1 tablespoon melted butter or margarine and spoon over potatoes. Bake 20-25 minutes or until heated through.

-- Courtesy of Joanna Wilkins (adapted from a recipe on Kraftfoods.com)

Roasted Vegetable Wraps

Serves 6

• 2 sweet potatoes

• 1 zucchini

• 1 yellow squash

• 1 cup grape tomatoes

• 1 small onion

• 1 bulb garlic

• 2 tablespoons olive oil

• Salt and pepper

• 1 avocado

• 2-4 ounces feta cheese

• 6 whole wheat tortillas

Heat oven to 400 degrees. Peel and chop potatoes and onions into bite-sized pieces. Peel garlic and leave cloves whole. Chop zucchini and squash into bite-sized pieces. Leave tomatoes whole. Place all vegetables on a baking sheet lined with aluminum foil. Drizzle with olive oil and season with salt and pepper to taste. Bake for 25-30 minutes or until vegetables are soft. Serve on tortillas with sliced avocados and feta cheese.

-- Courtesy of Joanna Wilkins