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!
This post has been updated — originally from 2009.