Korean candied sweet potatoes (goguma mattang) are fried pieces of sweet potatoes covered in a hard candy shell made of caramelized sugar!
Korean candied sweet potatoes, called goguma mattang (고구마 맛탕), is made from deep fried pieces of Korean sweet potato that’s candied with a golden brown, hard candy shell!
The hard, caramelized candy coating gives these Korean candied sweet potatoes a beautiful sheen and caramel color that’s makes this the perfect sweet potato dessert for fall or winter!
This is very similar to Japanese candied sweet potatoes, also called Daigaku Imo. The Korean version (Goguma Mattang) has a slightly thicker and hard caramelized coating that has a wonderful crunchy texture – almost like brittle.
Caramelized sweet potatoes are a simple, delicious Thanksgiving snack or dessert that’s easy to make and loved by all – children and adults!
Why this recipe works
- Deep frying the sweet potatoes make them tender and soft on the inside with a crispy outer layer.
- Coating these fried sweet potato pieces with a hard candy shell adds an amazing crunchy texture made of caramelized sugar!
- The hard candy coating keeps the sweet potatoes soft and fluffy on the inside and adds an amazing contrast in texture!
- If you prefer the caramel candy to have a deep, darker color with a slight hint of bitterness, let the caramel cook for a bit longer but keep a close eye on it. I find a subtle hint of bitterness adds depth of flavor and prevents it from tasting too sweet.
- Be careful not to cook the caramel too long as it can burn very quickly. Too much bitterness is an indication that it cooked for too long and burned.
Ingredients you’ll need
- Korean sweet potatoes – also called Japanese sweet potatoes. These have a purplish red skin and pale yellow interior. They also have less moisture than American sweet potatoes and are more similar in texture to chestnuts. They’re very sweet and tender when cooked.
- Sugar – Use plain white sugar for this recipe since we’re making a hard, caramel candy.
Step by step instructions
- Wash and dry the sweet potatoes thoroughly. Any remaining moisture on the sweet potatoes will cause splatter when fried.
- Cut the sweet potato into bite sized wedges. I like to cut them at an angle and then rotate the sweet potato for different shapes.
- Deep fry the sweet potato pieces at 340 degrees F for about 6 to 8 minutes or until they are golden brown and tender. Insert a toothpick to check for doneness. If your pieces are smaller, reduce the frying time.
- Make the caramel candy – Add the oil and sugar into a shallow pan and heat over low heat. Once the sugar starts to melt, slowly swirl the pan and allow the caramel to turn a golden brown color. Once it starts to bubble up on itself and foam, add the fried sweet potato pieces.
- Toss the sweet potato pieces with the caramel candy until each piece is coated.
- Lay them separately on parchment paper. Quickly sprinkle on black sesame seeds before the candy hardens. Serve when the candy coating hardens.
Frequently Asked Questions
Korean sweet potatoes, also called Japanese sweet potatoes or Asian sweet potatoes, have a red purplish skin with a pale, yellow interior. They’re very sweet and have a soft, fluffy texture when cooked and will turn a golden yellow color inside.
They’re different from American sweet potatoes because they have less moisture and a texture more similar to roasted chestnuts.
You can buy them in any Asian grocery store, including Korean, Japanese, and Chinese markets.
Yes the skin is safe to eat! Make sure to scrub the skin well and wash under running water. The skin contains fiber and and nutrients so keep the peel on if you prefer to.
These are best when consumed right away. The hard candy shell will start to soften if left out for too long.
You can refrigerate any leftovers in an airtight container but the hard caramel coating will turn into a sweet syrup, which is still delicious but different from the crunchy candy coating it had when first made.
Want more? Try these other recipes:
Korean Candied Sweet Potatoes (Goguma Mattang)
- 1 lb Korean or Japanese sweet potatoes – about two medium sweet potatoes
- ½ cup sugar
- 3 Tablespoons cooking oil – plus extra for deep frying
- 1 Tablespoon toasted black sesame seeds
- pinch of salt
- Wash and dry your sweet potatoes. Cut them into medium-small size pieces about 2 big.
- Add enough oil to a deep pot to fry the sweet potato wedges. Heat the pot over medium high heat until it reaches 340 degrees F. Add the sweet potato pieces and fry for 6 to 8 minutes or until golden brown and cooked through. Work in batches if needed. Adjust the cooking time based on the size of the sweet potatoes. Remove and let them drain on a paper towel.
- In a nonstick shallow pan, add 3 Tablespoons of oil into the pan, then pour the sugar directly over the oil. Heat the pan over low heat and avoid stirring or shaking the pan for now. (See Note 2)
- The sugar will start to melt and turn into a light syrup. Once the sugar is halfway melted, carefully and slowly swirl the pan so that the syrup doesn't burn. It will start to turn a golden caramel color and bubble up on itself. (Note: Be careful not to burn the caramel and watch it carefully as it can happen quickly. Burnt caramel will taste very bitter. )
- As soon as the caramel starts to bubble and foam, add in the fried sweet potato pieces and a pinch of salt. Quickly toss them together so each piece is coated in a layer of hard candy.
- Lay the candied sweet potato pieces on a layer of parchment paper, making sure they don't touch. Quickly garnish with black sesame seeds before the caramel candy hardens. Serve once cooled. (See Notes 3 and 4)
- Leftovers – these are best when consumed shortly after. You can store leftovers in an airtight container and keep it in the fridge. However, the hard candy shell will softened and turn into a sweet syrup (which is still delicious).
- I recommend using a nonstick pan for easier cleaning of the caramel.
- I strongly recommend laying the candied sweet potatoes on parchment paper. Otherwise, they are very sticky and may be hard to remove from your plates once it hardens.
- Be careful handling the candied sweet potatoes. The outer shell will still be very hot.
*Nutritional information is an estimate, calculated using online tools.