I also check by inserting a knife -- it should glide all the way through with ease.
In my opinion, sweet potatoes are a superfood on many levels. Not only are they incredibly nutritious (a 1-cup serving offers 65% of our daily requirement for vitamin C and as much as 700% of the recommended daily requirement for vitamin A), they also have a fairly low glycemic index of 17. They're also easy to find, easy to store, easy to cook, and they can function equally in sweet or savory recipes. But most importantly, they're delicious.
I like to roast my sweet potatoes to encourage their dense texture to soften and bring out their sweetness. Having a few already-cooked sweet potatoes in my refrigerator is like money in the bank, so I always roast extras while I'm at it. I also will sneak a few into the oven when I'm cooking something else for a more efficient way to roast them up.
Of course, the inevitable question arises when discussing sweet potatoes: what's the difference between sweet potatoes and yams? Read our post on this subject for more information, but basically most of the tubers you see marked as yams in the supermarket are sweet potatoes.
How to Bake a Sweet Potato in the Oven
What You Need
1. Preheat oven and wash the sweet potatoes: Preheat oven to 375°F. Scrub the sweet potatoes well and pat them dry with a dish towel.
2. Oil them up: Prepare squares of aluminum foil for as many sweet potatoes as you are roasting. Place each potato on a foil square and drizzle with a small amount of vegetable oil. Using your hands, rub the oil in a thin, even layer all over the potatoes.
3. Prick with a fork, wrap, and roast: Prick each sweet potato several times with a fork and wrap loosely in the foil. Be sure the foil is well-sealed. Place on a baking sheet and put them into the oven to roast.
4. Check for doneness: Depending on the size of your potatoes, it may take between 30 minutes to 1 hour for them to be done. Check at 30 minutes by squeezing one of the potatoes in a oven mitt protected hand and inserting a sharp knife or fork into the center. They should feel quite soft and the knife should easily glide all the way through. If not return to the oven and check again in 10 minutes.
5. Enjoy now or save for later: Enjoy your sweet potatoes in the many ways listed below or store them in the refrigerator for later. For storage, I leave them wrapped in their foil jackets on the counter until cool and then pop them into a plastic bag or glass container and put them into the fridge. They will keep for several days. Reheat in a microwave or toaster oven or use in recipes as needed.
Sweet potatoes are very forgiving and can roast at heats lower or higher than 375°F, so the most efficient way to cook them is to include them in the oven while you are cooking something else. If there isn't room for a tray, just tuck them in here and there directly on the rack but be sure to wrap them in foil as they can ooze liquid as they roast.
More on Sweet Potatoes:
• The Great Orange Taters (with recipe roundup)
• What Are Good Recipes for Using Up a Bunch of Sweet Potatoes?
• What's the Safest and Best Way to Cut Sweet Potatoes?
• Helpful Tip: Bake Up Some Sweet Potatoes!
• Comfort Me with Sweet Potatoes
(Images: Dana Velden)