OK, let’s get the confusing part over with. Those sweet, moist, typically orange roots we eat at Thanksgiving are sweet potatoes (Ipomoea batatas), not yams. A yam is something completely different. True yams (Dioscorea batatas), which are hard to find in grocery stores, are very starchy and dry. They have thick skins and white flesh and look like knotty roots. If you saw or tasted one, you wouldn’t mistake it for a sweet potato.
Now that we have that cleared up, the rest of the sweet potato story is pretty straightforward. Highly nutritious (they’re rich in beta carotene, vitamin C, and good carbohydrates), sweet potatoes have thin, edible skins and come in many shapes and colors, from the more common orangefleshed varieties to yellow- and even purple-fleshed ones. The deep-orange sweet potatoes are usually moister and sweeter than their yellow counterparts. I’m partial to a variety called Garnet, which has very dark flesh that’s especially sweet and creamy. Sweet potatoes come into season in late summer and are available right through spring, but they’re at their best in the fall and early winter.
At the market, choose firm, unblemished sweet potatoes and handle them with care, as they bruise easily. I am mystified by the admonition to use sweet potatoes soon after buying, because stored in a dark, cool place with good air circulation, they’ll keep for months. They will get drier, but they’re still perfectly good.
Bake sweet potatoes today, use them tomorrow
Baked sweet potatoes keep well in the fridge for a week or longer, so you can have them on hand to mash or use as twice-baked, in a soup, or just warmed up whole and brightened with a knob of herb butter or a spoonful of pesto.
Try different flavor partners
I like to liven things up by adding something pungent, spicy, sour, or salty to play counterpoint to sweet potatoes’ sweetness. Sharp cheeses pair well, as do sour cream, crème fraîche, and yogurt. Toasted pecans or walnuts are wonderful, as are sautéed or caramelized onions or shallots and roasted garlic. I find that all fresh herbs make good flavor partners, and citrus juice and zest of any kind add sparkle. Among condiments and spices, I like soy and ponzu sauces, balsamic vinegar, maple syrup, curry powder, ginger, and paprika (especially the smoked Spanish type, pimentón).