Q: What is the science behind adding baking soda to the cooking water?

A: When baking soda is added to the boiling water, it raises the pH level, making the water more alkaline. This increased alkalinity weakens the pectin in the potato cells, leading to a breakdown of the potato's surface. As a result, the edges of the potatoes become softer and rougher. When roasted, these rough edges crisp up more effectively, giving you that desirable crispy exterior.

Q: I've never cooked with potato starch; where do I find it in the supermarket?

A: In most stores, 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.

Crispy Roasted Sweet Potatoes

roasted potatoes tossed with remaining rosemary

Crispy Roasted Sweet Potatoes

Adapted from Cooking Smarter by Jeremy Scheck

Discover the secret to the crispiest roasted sweet potatoes—once you try it, there’s no going back to the traditional method!

Servings: 4 to 6

Prep Time: 15 Minutes

Cook Time: 55 Minutes

Total Time: 1 Hour 10 Minutes

Ingredients

Salt
½ teaspoon baking soda
3 large sweet potatoes (about 2½ pounds), unpeeled, cut into 1½-inch 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 and set an oven rack in the middle position.
In a large pot, bring 3 quarts 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.
Note: 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.
Note: 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

Per serving (6 servings)
Calories: 233
Fat: 7 g
Saturated fat: 1 g
Carbohydrates: 41 g
Sugar: 8 g
Fiber: 6 g
Protein: 3 g
Sodium: 463 mg
Cholesterol: 0 mg

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.