Getting the sweetest sweet potatoes isn't about picking out the ripest or most promising potatoes in the bunch. Nope! Rather, a little culinary magic trick will transform your toughest tubers into delicious treats. Here's how!
If you like your sweet potato casserole extra sweet, all you have to do is bake the sweet potatoes low and slow!
Raw sweet potatoes are mostly starchy fibers, but they also contain an enzyme that will break down the starch into sugar at certain temperatures. According to food scientist Harold McGee, this enzyme happens to work best when the sweet potato is between 135°F and 170°F.
Logically, the longer you can keep the sweet potato within this temperature range, the more starch will get converted to sugar. Steaming and boiling cook the sweet potato too quickly, but baking it in the oven at 350°F or lower is perfect. Sweet potatoes are done when they're soft all the way through.
If you're using the sweet potatoes in something like a casserole or a pie, you can bake the whole potatoes ahead of time and keep them for several days before using them in your recipe.
Give it a try!
(Oh, and by the way, that photo up top is from Pithy & Cleaver, where you can find this recipe: Sweet Potato Purée with Pecan Streusel. Yum!)
Related: Thanksgiving Sides: 5 Alternatives to Sweet Potato Casserole
(Image: Flickr member Maggie Hoffman licensed under Creative Commons)
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i cook mine in the crockpot. Some of the sugars burn a little at the bottom but they come out sooooo good!
YUM! These look delicious!!! I've made a lot of sweet potatoes, but never knew that low and slow would yield the sweetest result. THANKS!
Very interesting! I've been microwaving them for a couple minutes then tossing them in the oven to crisp up because of time constraints recently, but I will have to try this method one night where I don't have to have dinner ready in 20 minutes!
A trick I learned from Cook's Illustrated is to start them in a cold oven turned to 350F. That way they spend an even longer time in that sweet zone. It takes a while, but they turn out delicious!
So how long do they end up taking at 350? I suppose it depends on the size of the potato...Poke it with a fork to see?
I cook mine in the slow cooker too. I just add a little water to the bottom so they don't burn. Then I give the liquid to my dog in her dry food!
@molly_s - Plan on about an hour for whole potatoes (chunks will cook more quickly). And yes, poke with a fork to see if it's done!
I put mine on the BBQ -- no prep, just straight onto the grill at low heat for about an hour.
They're magnificent.
Good Eats Alton Brown says that slow oven "mute the sweetness" of the sweet potato, that 20minutes steamed over boiling water is best and fast. http://www.youtube.com/watch?v=Gk0jjDy3AVI (at time 06:59 on the video, he says this).
I tested it this week, made mash sweet potato in 1 minute (after the 20 minutes of steaming process of course) with just salt, pepper, and butter and served with korean short ribs and cucumber-avocado salad dressed in sesame dressing.... it was deliciously sweet. simple, and fast, and it was a lot easier to make and regular mashed potato...at least for me!
can't wait to try the sweet potato waffles, once we get a working waffle iron!
If the sweet potatoes convert the starches to sugars during the long, low baking process, then won't they be more moist and not as good for a mashed potatos type dish. I like my sweet potatoes on the dry side, so wouldn't I be better off microwaving them?
lona - no! you keep them whole (just give them a scrub), make a slit or puncture a few holes in the SPs then bake them. they aren't too dry or too moist. i've whipped them with lime or sugar and cream and they're dry. you can also use the mash as a sweet potato pie base. yum!
this is exactly what i do - never knew it was the right way to do them!
I'm impatient so I cut mine into chunks for faster cooking, and toss them with olive oil in a hot oven (like 400). Then a bit before they're done, I add in some maple syrup and toss them a bit so they get even more caramelized. So delicious.
I've always chopped mine into pieces (peeled), seasoned and tossed in olive oil, then roasted at 150-180C along with everything else for a roast dinner. They go squooshy and slightly caramelised - yum :-)