Crispy Sweet Potato Japanese Long Fries

Crispy on the outside and tender on the inside, these Sweet Potato Japanese Long Fries are a savory twist on classic fries. Made with mashed sweet potatoes, herbs, and cornstarch for the perfect crunch, they’re an easy and flavorful side or snack.

If you love crispy, golden fries with a tender center, these Sweet Potato Japanese Long Fries are about to become your new favorite side dish. Made from mashed sweet potatoes shaped into long, fry-like strips, this recipe combines the natural sweetness of sweet potatoes with savory herbs and a light, crisp exterior. The result is a perfectly snackable fry that’s crispy on the outside, soft on the inside, and completely irresistible.

These fries are inspired by the Japanese long fry trend, but made easy for home cooks—no special tools required. They’re perfect for pairing with dipping sauces, adding to a burger night spread, or serving as a fun, elevated appetizer.

Why You’ll Love These Sweet Potato Fries

• Crispy outside, tender inside: The cornstarch creates that perfect crunch without heavy breading.
• Naturally flavorful: A blend of herbs and spices enhances the sweet, earthy flavor of the potatoes.
• Freezer-friendly: You can prep the fries ahead of time and fry them right before serving.

Ingredients

• Sweet potatoes: The base of the recipe, providing natural sweetness and color. Look for firm, medium-sized potatoes for easier cutting. You can substitute with Japanese yams or purple sweet potatoes for a fun twist.
• Garlic powder and onion powder: Add depth and savory flavor to balance the sweetness.
• Italian herb seasoning: Brings in aromatic notes of oregano, thyme, and basil. You can swap this for herbes de Provence or your favorite all-purpose seasoning.
• Paprika: Adds a subtle smoky flavor and beautiful color. Smoked paprika works great for a bolder flavor.
• Salt and black pepper: Enhance all the other flavors and bring balance to the dish.
• Cornstarch: The secret to achieving that crisp, golden exterior. Arrowroot starch or potato starch also work well.
• Frying oil: Tallow adds incredible richness and crispness, but you can also use avocado oil, vegetable oil, or peanut oil depending on your preference.

Instructions

1. Peel and chop the sweet potatoes, then boil until fork-tender.
2. Transfer to a large bowl and let them steam for a few minutes to release excess moisture.
3. Mash until smooth, then mix in the seasonings and cornstarch until well combined.
4. Press the mixture evenly into a parchment-lined pan and freeze for 30 minutes.
5. Slice into long, thin strips to create your “fries.”
6. Heat the oil to 375°F and fry the fries in small batches for 2–3 minutes until crisp and golden.
7. Transfer to a paper towel-lined rack to drain, then season lightly and serve warm.

Serving Suggestions

Serve your Sweet Potato Japanese Long Fries with a side of garlic aioli, spicy mayo, or honey butter for dipping. They’re also incredible topped with flaky salt and a sprinkle of Parmesan cheese for a little extra indulgence.

Tips for Success

• Don’t skip the freezing step—it helps the fries hold their shape while frying.
• Keep your oil hot! If it cools down, the fries can fall apart or absorb too much oil.
• These can easily be made ahead and fried right before serving for the best texture.

Sweet Potato Japanese Long Fries

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Crispy on the outside and tender on the inside, these Sweet Potato Japanese Long Fries are a savory twist on classic fries. Made with mashed sweet potatoes, herbs, and cornstarch for the perfect crunch, they’re an easy and flavorful side or snack.

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Prep Time:25 minutes mins

Cook Time:20 minutes mins

Course: Side Dish

Servings: 4

Ingredients

• 2-3 Sweet Potatoes about 1.5 lbs
• 2 tsp garlic powder
• 2 tsp onion powder
• 2 tsp Itialian herb seasoning
• 1 tsp paprika
• 1 tsp salt
• 1 tsp pepper
• 1/4 cup cornstarch.
• Frying Oil I love tallow

Instructions

• Peel the sweet potatoes, then chop into small pieces. Add to a saucepan filled with boiling water over medium high heat to boil for 8-10 minutes, until fork tender.
• Use a slotted spoon to transfer the softened potatoes to a large mixing bowl. Let steam in the bowl for 5-10 minutes.
• Use a potato masher to make the potatoes into mashed potatoes.
• Add the spices and cornstarch. Mix with a spatula until combined.
• Transfer the mashed potatoes a parchment lined quarter sheet pan (or 9×13 pan). Press into an even layer.
• Freeze for 30 minutes. If making in advance, you can freeze up to the day prior.
• Transfer potatoes to a cutting board and use a kitchen knife to slice into 1/2″ thick strips.
• Heat up 3-4″ of frying oil in a large skillet over medium high heat.
• Once oil has reached 375F, work in small batches of 3-4 long fries at a time to fry until deeply golden, about 2-3 minutes. If you find the fries are falling apart, it’s likely the oil is not staying hot enough.
• Use a slotted spoon to transfer the golden fries to the paper towel lined baking rack to drain excess oils.
• Then Enjoy!