Glazed Japanese Sweet Potato Recipe Daigaku Imo

In my version, I like to use a three-step process of steaming, frying, and glazing the sweet potatoes. This cooking method creates a lasting crisp exterior while the interior remains tender and moist. It may take a little more prep time, but the results are definitely worth it!

Why This Recipe Works?

Steaming the Japanese sweet potatoes first gives them a soft and creamy texture. Deep frying the steamed sweet potatoes gives them a uniform golden-brown crust, which keeps them from falling apart when you glaze them. Glazing the outside of the sweet potatoes with a crisp candy coating instead of double frying them keeps them from getting dry and mealy and results in ideal textures on the inside and outside.

Ingredients for Glazed Japanese Sweet Potato

Japanese Sweet Potatoes - Japanese sweet potatoes have red skin and yellow flesh, with less moisture and more starch than their North American relatives. This makes them well suited for frying. Rice Syrup - rice syrup is made by saccharifying the starch in rice, which converts it into sugars (primarily maltose). At room temperature, it is very thick (like cold honey) and has a slick surface that gives the Daigaku Imo a beautiful, shiny, lacquer-like coating that adheres well to the crispy fried flesh and smooth skin. Sugar - Maltose tastes half as sweet as regular sugar, so I like to add a bit of evaporated cane sugar (sucrose) to the mix to give it a slightly sweeter taste. If you can’t find evaporated cane sugar, white sugar can be substituted. If you want yours to taste less sweet, you can just use the rice syrup. A light sprinkling of salt can help balance out the candy-like sweetness. Black Sesame Seeds - The black sesame seeds add some visual contrast and contribute to the crisp texture of the candy coating while imbuing a wonderfully nutty flavor to the mix.

How to Make Daigaku Imo

The first thing you need to do is prepare the Japanese sweet potatoes. I start by giving them a good wash, being careful not to scrub the skin off. Then I trim both ends off of each one and cut them up using rangiri. To do this, cut off a chunk of sweet potato at a 45-degree angle and then turn it 90 degrees before cutting off another chunk at the same angle. This should allow you to cut the tapered tuber into pieces that are roughly the same size and thickness. As you cut the sweet potato, put the pieces into a medium bowl of cold water to keep them from oxidizing. Fill a heavy-bottomed pot with 2 inches of vegetable oil and preheat it to 340 degrees F (180 C). Rinse any excess starch off the cut sweet potatoes, drain them, and then place them in a frying pan with ¼ cup of water. Cover the pan with a lid, and then bring the water to a boil over medium-high heat. Steam them for another 5-6 minutes, or the time it takes for most of the water to evaporate. Remove the lid and allow any remaining water to evaporate. Once the sweet potatoes are no longer wet, add them to the preheated oil and deep fry them for about five minutes or until they’re golden brown. Be sure to turn them over regularly so they brown evenly. About 2 minutes before the sweet potatoes are done, add the rice syrup and sugar to the frying pan you used for steaming and heat the mixture until the sugar is melted. Use tongs to drain and transfer the fried sweet potatoes directly into the syrup, and then toss everything together to coat the Daigaku Imo evenly. The mixture should be very sticky to ensure the sugar forms a crisp shell, but if it becomes impossible to mix or it seems like it’s starting to burn, add a spoonful of water to loosen things up. Finish the Daigaku Imo by tossing in the black sesame seeds. To balance the sweetness, you can also sprinkle in a pinch of flaky salt.