When I was still a high school student, there was this shop that specialised in Japanese Candied Sweet Potato Chips on the street in Namba (one of the city centres in Osaka). Although there was always a long queue, I did not mind waiting as I loved watching the sweet potatoes cooked in a big frying-pan with super hot oil and coated in sticky candy. The sugar-coated sweet potato chips were golden and shiny. The outside was crunchy, and the inside was soft and flaky. Off course, they were SWEET! They were a perfect street snack for us – young high school girls.
Japanese Candied Sweet Potato is called Daigaku Imo in Japan, whose direct translation is “University Potato”. This is one of my most missed Japanese snacks.
First, I wanted to replicate the Namba shop’s, but soon I realised it was too hard to do so with our week electric stove. In addition, I always feel guilty using that much oil…
Another thing that I found it difficult to achieve was to make the candy crispy. I know some people like it soft (that’s also nice), but in my memory, the Namba shop’s chips were super crunchy, and that was why I loved theirs so much.
After some research and several trials (which included eating so much sugary sweet potato ships, OMG!), I finally found the way.
In this recipe, you can just pan-fry sweet potato with a small amount of oil, instead of deep-frying. To achieve the crunchiness of the candy, I use “Icy Cold Water” to harden the candy.
The ingredients are so simple, but there are some keys to make this recipe a success.
- Use purple skin sweet potato, which is firmer than the orange one.
- Pat-dry sweet potato very well.
- Lie the chips in single layer in a frying-pan.
- Do not touch the chips while pan-frying (touch only once when flipping the chips).
- Candy mixture – Wait until the caramel becomes golden brown.
It is not difficult to make this. In fact, you can make this anytime you feel like it. Just remember the key notes to receive the best result of this recipe.
I have to say, this is a really dangerous snack… Once you start, you cannot stop. Sweet, Crunchy, Flaky… Well…, at least sweet potatoes are a vegetable, aren’t they?!
- 250g of Purple Skinned Sweet Potatoes
- 1 Tablespoon of Oil
- 2.5 Tablespoons of Sugar
- 1 Tablespoon of Water
- 1 Teaspoon of Soy Sauce
- 2 Teaspoon of Sesame Seeds
- Cold water with some ice cubes in a bowl
- Preparation for sweet potato. Cut sweet potato into 1cm thick/width of finger-sized chips, leaving the skin on. Soak them in water (not included in the ingredients’ list above) for about 15 minutes. This method is to remove the harsh taste of sweet potato. Pat-dry the sweet potato chips very well with paper towels.
- Place the sweet potato chips in a frying-pan and toss with oil. Lie the chips flat in single layer. If you are using a small frying-pan and cannot lie all of the chips in a single layer, I would recommend using 2 frying-pans. Place the frying-pan over a medium-high heat. Once the oil gets hot and starts making some “cooking” sounds, turn the heat to low-medium. Keep cooking for about 5 minutes each side, or until both sides become nicely browned. Do not touch often! Just flip over the chips once while cooking. Once they are cooked, transfer them to a plate.
- Now we make the candy mixture. Wipe the remaining oil from the frying-pan with paper towels. Place sugar and water. Heat it over a medium heat. When the mixture has become golden and started to caramelised (it will take about 5 minutes), add soy sauce gently from the edge of the frying-pan, and then add the sweet potato chips. Toss the chips to coat in the candy.
- Make icy cold water with some ice cubes ready in a bowl. Pick up the candy-coated chip one by one with either a tong or chopsticks and dip it into the cold water for 3 seconds. Shake the excess water off from the chip and transfer it to a plate. Continue the process. Sprinkle sesame seeds over the chips to serve.
- I recommend serving them straight away while the caramel is crispy.