Crispy Roasted Sweet Potatoes
This post may contain affiliate links. Read my full disclosure policy.
These crispy roasted sweet potatoes are creamy and tender inside with deeply golden, craggy edges. A few simple tricks make all the difference.
Have you ever tried to make perfectly crispy roasted sweet potatoes, only to end up with potatoes that are disappointingly soft? Because sweet potatoes contain more sugar and moisture than regular potatoes, they tend to soften rather than crisp in the oven. This recipe, adapted from Cooking Smarter by Jeremy Scheck, uses a few clever tricks to deliver the crispiest, most delicious roasted sweet potatoes ever.
First, the potatoes are par-boiled in salted water with a little baking soda, which softens the surface and creates rough, craggy edges that brown beautifully in the oven (the same technique I use for my crispy potato wedges). They’re then tossed with olive oil, seasonings, and potato starch, which forms a light coating that gets wonderfully crisp as they roast. The result is sweet potatoes that are creamy and tender inside with deeply golden, crispy edges.
These crispy roasted sweet potatoes make an easy side for everything from grilled chicken and baked chicken thighs to glazed pork tenderloin.
“I didn’t think that crispy sweet potatoes were possible, but here they are. I will be making these gems again and again. Thank you, Jenn.”
What You’ll Need To Make Crispy Roasted Sweet Potatoes
- Baking Soda: Makes the boiling water alkaline, which helps break down the potatoes’ surface so the edges become slightly softened and rough. Those craggy edges will crisp up beautifully in the oven.
- Sweet Potatoes: Look for firm, evenly shaped sweet potatoes with smooth, unblemished skin; there is no need to peel them.
- Potato Starch: Serves as a coating that crisps up beautifully as the potatoes roast. In most stores, you can find it in the baking aisle alongside other starches and thickeners like cornstarch. It may also be in the gluten-free or international foods aisle, especially within the Kosher or Asian sections. Corn starch can be substituted if necessary.
- Olive Oil: Assists in achieving a golden, crispy texture and adds richness.
- Chopped Fresh Rosemary: Complements the sweetness of the potatoes. Feel free to experiment with your favorite herbs—fresh thyme would also work well.
- Jump to the printable recipe for precise measurements
Step-By-Step Instructions
Step 1: Par-boil the sweet potatoes. Bring a large pot of salted water to a boil and add the baking soda, followed by the sweet potatoes. Par-boil until the potatoes are tender around the edges but still hold their shape. Drain the potatoes thoroughly.
Step 2: Season and roast. Transfer the drained sweet potatoes to a rimmed baking sheet. Add the potato starch, olive oil, salt, pepper, and rosemary, and gently toss to coat, roughing up the edges a bit. Spread out and roast until deeply golden and crisp. Turn off the oven and let the potatoes rest inside briefly to crisp up even more.
Step 3: Serve. Sprinkle with more rosemary, taste and adjust the seasoning if needed, and serve hot.
More Sweet Potato Recipes You’ll Love
Crispy Roasted Sweet Potatoes
Ingredients
- Salt
- ½ teaspoon baking soda
- 2½ pounds sweet potatoes (about 3 large), unpeeled, cut into 1½-inch (4-cm) chunks
- 2 tablespoons potato starch (see note)
- 3 tablespoons olive oil
- 1 tablespoon chopped fresh rosemary, divided
- ¼ teaspoon freshly ground black pepper
Instructions
- Preheat the oven to 450°F (230°C) and set an oven rack in the middle position.
- In a large pot, bring 3 quarts (3 L) of water to a boil. Stir in 1 tablespoon of salt and the baking soda. Add the potatoes and boil for 10 minutes.Drain the potatoes thoroughly.
- Directly on a rimmed baking sheet (avoid using foil as the potatoes may stick), toss the par-boiled potatoes with the potato starch, oil, ½ teaspoon of salt, half of the rosemary, and the pepper. Roast in the preheated oven for 35 minutes, stirring once midway through roasting. After roasting, turn off the oven but leave the potatoes inside for an additional 10 to 15 minutes.
- Remove from the oven and sprinkle with the remaining rosemary. Taste and adjust the seasoning with salt, if necessary. Transfer the sweet potatoes to a platter and serve.
Notes
- In most supermarkets, you can find potato starch in the baking aisle alongside other starches and thickeners like cornstarch. It may also be in the gluten-free or international foods aisle, especially within the Kosher or Asian sections. Some stores that have distinct sections for natural or organic foods might also stock potato starch there. If you're having difficulty finding it, ask a store employee.
- The sodium content provided in the nutritional section for the potatoes is based on the assumption that about ½ teaspoon of salt is absorbed during boiling in salted water. This is just an estimate, and the actual sodium level can vary.
Nutrition Information
This website is written and produced for informational purposes only. I am not a certified nutritionist and the nutritional data on this site has not been evaluated or approved by a nutritionist or the Food and Drug Administration. Nutritional information is offered as a courtesy and should not be construed as a guarantee. The data is calculated through an online nutritional calculator, Edamam.com. Although I do my best to provide accurate nutritional information, these figures should be considered estimates only. Varying factors such as product types or brands purchased, natural fluctuations in fresh produce, and the way ingredients are processed change the effective nutritional information in any given recipe. Furthermore, different online calculators provide different results depending on their own nutrition fact sources and algorithms. To obtain the most accurate nutritional information in a given recipe, you should calculate the nutritional information with the actual ingredients used in your recipe, using your preferred nutrition calculator.
Gluten-Free Adaptable Note
To the best of my knowledge, all of the ingredients used in this recipe are gluten-free or widely available in gluten-free versions. There is hidden gluten in many foods; if you're following a gluten-free diet or cooking for someone with gluten allergies, always read the labels of your ingredients to verify that they are gluten-free.
See more recipes:
Add a Comment
This site uses Akismet to reduce spam. Learn how your comment data is processed.
Made these last night as a side dish to go with leftovers. I ended up skipping the leftovers and eating half the pan for my dinner! Delicious. Crispy on the outside, soft on the inside. Rosemary was a nice addition. Followed the recipe exactly. Wonderful way to make sweet potatoes. I plan on cutting the potatoes into thick wedges and making sweet potato steak fries the next time I do burgers.
Superb! Used cornflour as I didn’t have any potato starch and it worked like a dream!
Delicious! Quick question for next time: can you use parchment paper to line the rimmed baking sheet for easier cleanup?
I worry the parchment would burn at such a high temp. Sorry!
Just to let everyone know… Reynolds now makes a nonstick aluminum foil. It’s fantastic when you want to line a pan, but may be worried about things sticking.
Finally a way to make crispy sweet potatoes! My family devoured them straight off the pan.
Hi Jenn,
Do you think this would work on butternut squash? I’m trying to get my husband to try and like it! LOL
Thanks,
Kristen Berry
Hi Kristen, You’re not the first to ask that, and I definitely plan to test it out – I’ll let you know once I do.
Thanks Jenn!
Mine did not come out crispy and I did use potato starch. Not sure where I sent wrong. Not enough potato starch? Not cooked long enough? Any ideas?
Hi Timothy, I’m sorry these didn’t come out crispy for you! Did you make any adjustments to the recipe?
Reflecting back I did use avocado oil. In the meantime I’ll try it exactly your way since your recipes are soooo good (have both of your books). I’ll blame it on user error!!
Hope you have better luck the second time around!
Could I add garlic cloves to this recipe? If so, when?
Hi Jean, I’d be hesitant to add garlic cloves because of the high cooking temperature. I worry they’d burn.
Can the finished dish be frozen and reheated for T Day without losing crisp? We have 16 guests. I need a head start!
Hi Bob, Unfortunately these don’t reheat particularly well. Sorry!
Love the recipe.
I have sweet potatoes/yams on hand but not fresh rosemary. Since it’s a 20 minute drive to a grocery store (so 40 minutes in total) for just the one item isn’t going to happen this week! Will dried rosemary be okay to use or would it be better to wait until my next trip to town to include fresh rosemary with a regular grocery shop? The sweet potatoes won’t come to any harm to wait another week…but oh my I’m keen to give this recipe a try! It just looks and sounds like such a winner!
Thanks for your fabulous website Jenn and the cooking science of the “why” behind the “how’. Love learning!
Hi Susan, These are delicious even without the rosemary, but you can use other herbs as well. I think fresh or dried thyme would both be delicious. Dried rosemary is a bit tricky because it has a woody texture; if you’d like to use it, try to crush/grind it before adding.
If I can’t find potatoe starch, would cornstarch or arrowroot be an alternative substitute?
I’ll rate the recipe after I make this.
Hi KarenAnn, You can use cornstarch but the potatoes won’t be quite as crispy. Most supermarkets carry potato starch—it’s worth seeking out if you can get it.
One of my local stores carries potato starch, different flours, rice, beans, etc in the bulk section, so I can buy a little or a lot of these things.