White potatoes have plenty of nutritional value, but sweet potatoes — a good source of fiber that’s also high in calcium, folate, potassium and beta-carotene — have them beat. One caveat: steam your sweet potatoes just until they become tender. Overdo it and they’ll turn to mush.

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Sweet potato, grilled corn and black bean salad with spicy cilantro dressing. This recipe swaps sweet potatoes for the more traditional white potatoes and loses the standard recipe’s abundant mayonnaise in favor of a dressing high in flavor and low in fat. The Associated Press

SWEET POTATO, GRILLED CORN AND BLACK BEAN SALAD WITH SPICY CILANTRO DRESSING

Start to finish: 45 minutes (30 minutes active)

Servings: 6

1 1/2 pounds sweet potatoes, peeled and cut into 1/2-inch chunks

1 clove garlic

1/2 chipotle pepper in adobo sauce

1 small shallot, coarsely chopped

1 cup chopped fresh cilantro

1 cup seasoned rice vinegar

Salt

4 ears corn, husked

15 1/2-ounce can black beans, drained

4 scallions, white and green parts, thinly sliced

Heat the grill to medium. In a medium saucepan fitted with a steamer basket, bring 2 inches of water to a boil. Add the sweet potatoes, cover and steam until just tender, about 8 minutes. Transfer the potatoes to a bowl.

Meanwhile, in a blender, combine the garlic, chipotle, shallot, cilantro and vinegar. Puree until smooth.

Taste, then season with salt. When the potatoes are done, pour half of the dressing over them, then toss well. Set aside to cool.

While the potatoes cool, prepare the corn. Mist the corn with cooking spray, then grill, turning often, until the ears are lightly browned in spots on all sides, about 10 minutes. Remove the corn from the grill and set aside to cool until easily handled. Cut the kernels from the cobs. To do this, one at a time stand each ear on its wide end, then carefully saw down the length of the cob on all sides. You should have at least 2 cups of kernels. Stir the corn kernels, beans and scallions into the potatoes, adding additional dressing as desired. Taste, then adjust seasoning.

Nutrition information per serving: 260 calories; 20 calories from fat (8 percent of total calories); 2.5 g fat (0 g saturated; 0 g trans fats); 0 mg cholesterol; 54 g carbohydrate; 9 g fiber; 17 g sugar; 9 g protein; 1250 mg sodium.

I’ve cast black beans and corn in support of the sweet potatoes. I like black beans for their robust taste and their staying power. (They do a fine job of filling you up.) Like all legumes, black beans are low in calories and high in protein and fiber, and they boast an assortment of important nutrients.

Corn, of course, is in no need of hype. It’s just about everyone’s favorite summer vegetable. But corn is at its best when it’s fresh, fresh, fresh! Corn’s natural sugars start to turn into starch the minute it’s harvested. The challenge is to safeguard its natural sweetness. If you live near a farm stand or a farmers market, buy your corn in the morning, then refrigerate it as soon as you get home and cook it as soon as possible.

Typically, truly fresh corn is so good you can eat it raw. Boil it and brush it with butter and you have a dish fit for a king. But grilling the corn, as we do here, takes it to an even higher level. Somehow this process amps up the flavor and decreases the need for fat.

In fact, with the exception of the spray used to coat the corn before grilling, there’s no oil in this recipe. How’d I manage that little trick? By composing a dressing so flavorful — the keys are chipotle, cilantro and garlic — no one notices the lack of fat. The chipotles (or smoked jalapeno chilies) are the crucial ingredient. You can find them in your supermarket simply dried or in an adobo sauce. I prefer the adobo, made of tomato and vinegar, because it adds a lovely flavor of its own. The chili’s heat is counter-balanced with the slight sweetness of the seasoned rice vinegar and by the sweet potatoes. (If you happen to be a cilantro hater, substitute basil or mint.)

One final note: toss the sweet potatoes with the dressing while they’re still warm, which helps them to absorb the dressing and become deeply flavored.