Sweet potatoes are ambassadors of fall

Homemade sweet potato gnocchi. BY JACK CLEMONS
September 12, 2011

What’s the difference between a sweet potato and a yam? As it turns out, quite a bit. The origins of the word yam can be traced to an African expression that means “something to eat.” Over time, the word yam has been used to describe a range of things to eat, including yams, sweet potatoes, taro and oca (all tubers and all different vegetables). And, it may surprise you to learn that sweet potatoes are not a member of the nightshades like white potatoes; they belong to the morning glory family - you’ve probably seen their bright green ornamental vines in flower pots.

Sweet potatoes have been cultivated for centuries, and evidence of their wild ancestors has been dated to 8,000 BC. From before the time of the Incas, sweet potatoes were a staple food throughout the tropical Americas. Hawaiian and Maori records date the arrival of sweet potatoes in their islands during the 13th century. Europeans who traveled with Columbus to Haiti tasted sweet potatoes known as batata.

Introduced across the globe from Asia to India to Africa, sweet potatoes thrive in areas with hot climates. They became a valued food source during the Revolutionary War and Civil War in the southern United States: they grow quickly and remain underground, hidden from deliberate devastation to farms and vegetable gardens.

The sweet potatoes popular today are typically about six inches long, elongated with slightly pointed ends, reddish-brown skin and deep orange flesh. These are the soft type, so called because their pulp becomes soft and moist when cooked. They’re an excellent source of dietary fiber and vitamin A in the form of beta carotene.

With the faintest hint of chill to the morning air last weekend, we were attracted to a basket of rosy-skinned sweet potatoes at the market. Our daughter-in-law Bridget suggested sweet potato gnocchi, and we picked out several pounds of fresh sweet potatoes. A tricky combination of potato and flour, gnocchi is best when the dough is light and tender, using the least amount of flour to hold things together. In order to make the recipe work with sweet potatoes, I added an extra step: after draining but before pureeing the cooked potatoes, toss them in a dry skillet over a very low heat to remove all the excess moisture from the pulp.

Rolling and cutting the dough was easy enough; the most awkward step was sliding the small pieces off the tines of a fork to create the gnocchi’s signature creases. As you can see from the photo, mine are a bit more irregular than the prepackaged variety. The sauce was a simple swirl of browned butter and parsley, adding color and richness to the fluffy texture.

Sweet potato fries and chips are easy to make in the oven, keeping the calories down. The french fries are tossed in olive oil and baked. Depending upon the main course, you can vary their flavor with a dusting of spice (cumin or onion powder, for example). Or, you could highlight their sweetness with a sprinkle of cinnamon sugar and serve them as dessert. To make sweet potato chips, follow a similar technique, substituting cooking spray for the oil. The key to success in both cases is to keep the size of the pieces absolutely uniform - no thin spots to burn.

Consider reaching for sweet potatoes the next time you make a stew or soup that calls for white potatoes. Or make sweet potatoes the star of the soup as in the creamy, smooth puree in the recipe below. As I planned this article, Bridget offered her version of balsamic mashed sweet potatoes, but I’m waiting for Thanksgiving when she’s promised to make them for us.

Sweet Potato Gnocchi
1 lb sweet potatoes
1 egg yolk
1/4 t nutmeg
1/3 C white flour
1/3 C whole wheat flour

Coat a baking sheet with parchment paper; set aside. Peel the potatoes and chop into large chunks. Place them in a saucepan with water to cover. Bring to a boil and then reduce to a simmer. Cook until fork tender, about 20 minutes. Drain the potatoes and return them to the empty saucepan. Place over a very low heat and cook until all traces of moisture have evaporated, about 8 minutes. Using a ricer or a food mill, puree the potatoes until smooth, placing the pulp in a large mixing bowl. Stir in the egg yolk and nutmeg; set aside. Combine the flours and sprinkle two-thirds of the flour mixture over the potatoes. Fold gently, just until incorporated. Pinch off a small piece of dough and roll it into a tube slightly larger than your thumb. If it doesn’t hold its shape, add the remainder of the flour and stir. Roll out the dough on a lightly floured surface into 1/2-inch thick ropes. Cut off pieces one inch long and arrange on the parchment paper without letting the pieces touch. (Note: you can dent the center of each piece with your thumb or flip each piece off the tines of a fork to create ridges). Cover with paper towel and refrigerate for one hour (Alternatively, freeze the gnocchi and collect the pieces into a zip-top bag).
When ready to cook, bring salted water to a boil in a large saucepan. Add the pieces and cook one minute more after they float to the top; do this in multiple steps to avoid crowding the pot. Remove cooked gnocchi with a slotted spoon directly into a skillet of melted butter or other sauce.

Sweet Potato Oven Fries
2 sweet potatoes
3 T olive oil

Preheat oven to 450 F. Peel the sweet potatoes and slice into strips the length of the potato about one-half inch wide and thick (or use a mandoline). Dry with a paper towel and place on a baking sheet. Sprinkle generously with salt and pepper, to taste. Drizzle with olive oil and toss to coat completely. Bake for 10 minutes; turn fries and bake an additional 10 minutes. Yield 2 to 3 servings.

Baked Sweet Potato Chips
1 sweet potato
canola or olive oil spray

Preheat oven to 400 F. Peel the sweet potato and slice 1/8 inch thick with a mandoline. Arrange the chips on a cookie sheet and spray with oil on both sides. Bake for 10 minutes; flip the chips and bake another 5 to 7 minutes. Season with salt, to taste.

Sweet Potato Soup
1 T olive oil
1 chopped onion
1 1/2 C chopped carrots
1 peeled, chopped sweet potato
1 C orange juice
2 C vegetable broth
salt and pepper, to taste as needed
1/4 C sour cream
snipped chives

In a soup pot or large saucepan, sauté onions and carrots in oil until glistening, about 5 minutes. Stir in sweet potato, juice and broth; bring to a boil. Reduce heat and simmer over medium heat until vegetables are tender, about 20 minutes. Puree soup with an immersion blender or in a food processor. Add salt and pepper, to taste. Serve garnished with sour cream and chives.