Chef Takumi
Japanese Potato Salad (ポテトサラダ, Poteto Sarada)
Japanese potato salad asks for warm floury potatoes, salted cucumber, a little ham, and Kewpie folded in after the heat has faded. Keep it rough, tangy, and quietly generous.
Culinary Explorer
A cooking platform built around craft, culture, and the stories behind what we eat.
Candied Japanese Sweet Potatoes (大学芋, Daigakuimo)
Created by
Daigakuimo is simple student comfort: sweet potato cut stout, fried until the corners take color, then turned in a soy-sugar syrup that sets shiny instead of sticky.
Side Dishes
Japanese
Comfort Food
Weeknight
Picnic
20 min
Active Time
25 min cook•45 min total
Yield4 servings
Daigakuimo begins with a sweet potato that already wants to be dessert. In autumn, when satsumaimo are at their prime, the flesh is yellow, dense, and quietly sweet. All we do is cut it into rough angles, fry it, and give it a thin coat of soy-sugar shine.
This dish looks like confectionery, so people suspect a thermometer and a brave heart. No. The first secret is gentler than that: cook the potato through at a moderate heat, then give it one hotter minute so the corners crisp. The skin stays on because it holds the piece together and gives that fine purple edge against the gold flesh. Nothing hidden, nothing fussy.
The syrup is the place to pay attention. It should bubble slowly and look glossy before the soy goes in, thick enough to cling but not dark enough to taste burnt. That is the meeting point: hot potato, thick ame, black sesame. If the glaze runs, wait a little longer. If it smells like caramel, you went too far, and the sugar has started teaching the class without permission.
Daigakuimo sits happily between side dish and sweet snack, the kind of thing that fits a weeknight plate, a bento corner, or a picnic box once cooled. Serve fewer pieces than the bowl could hold. Leave it room, let the black sesame show against the glaze, and the dish reads exactly as it should: cheerful, plain, and honmono.
Daigakuimo means university potatoes, and most accounts place the sweet in Tokyo in the early twentieth century, especially around the Kanda and Hongō student districts. It became tied to students because satsumaimo was cheap, filling, and sweet; one widely repeated story says students sold the fried potatoes in syrup to help cover school expenses. The sweet potato reached Satsuma from the Ryūkyū Islands around the turn of the eighteenth century, and scholar Aoki Konyō promoted its cultivation near Edo after the Kyōhō famine of 1732.
The technique, the tradition, and the story behind every dish.
Discover Culinary ExplorerIngredients
Japanese sweet potatoes (satsumaimo)
Quantity
2 medium (about 600g)
scrubbed, skin left on
cold water
Quantity
for soaking
neutral oil
Quantity
enough for 5 cm / 2 inches in the pot
for deep-frying
sugar
Quantity
80g (about 6 tablespoons)
water
Quantity
2 tablespoons
soy sauce
Quantity
1 teaspoon
toasted black sesame seeds
Quantity
2 teaspoons
| Ingredient | Quantity |
|---|---|
| Japanese sweet potatoes (satsumaimo)scrubbed, skin left on | 2 medium (about 600g) |
| cold water | for soaking |
| neutral oilfor deep-frying | enough for 5 cm / 2 inches in the pot |
| sugar | 80g (about 6 tablespoons) |
| water | 2 tablespoons |
| soy sauce | 1 teaspoon |
| toasted black sesame seeds | 2 teaspoons |
Equipment Needed
- •Heavy pot or wok for deep-frying
- •Frying thermometer, or a dry wooden chopstick for checking steady bubbles in the oil
- •Ami shakushi, a Japanese wire skimmer, or a spider strainer
- •Wide skillet for the syrup
- •Oiled parchment or a lightly oiled plate for cooling
Instructions
- 1
Cut and soak
Scrub the satsumaimo well and leave the skin on. Cut them into stout 4 cm chunks using rangiri, the rolling cut: turn the potato a quarter turn after each diagonal cut so you get irregular angled faces. Soak the pieces in cold water for 10 minutes. This rinses away surface starch, keeps the cut faces clean, and helps the corners fry crisp instead of scorching before the center is tender.
Rangiri is not decoration. The angles make more corners for the oil to crisp and more faces for the syrup to cling to. - 2
Dry completely
Drain the sweet potatoes and dry them thoroughly with a clean towel, especially around the skin and cut edges. Water in hot oil spits, and wet surfaces cool the oil at the very place you want quick frying. Dry pieces fry cleanly. Wet pieces hesitate.
- 3
Fry until tender
Pour oil into a heavy pot to a depth of about 5 cm / 2 inches and heat it to 160 C / 320 F. Fry the sweet potatoes in batches so they have room to move, turning them now and then, for 8 to 10 minutes. They are ready for the final heat when a skewer slides in without force and the edges are just beginning to turn gold. Moderate oil gives the dense center time to cook before the outside darkens.
- 4
Crisp the corners
Raise the oil to 180 C / 355 F and fry the pieces for 1 to 2 minutes more, just until the corners deepen in color and the skin looks a little wrinkled. This hotter finish crisps the outside without drying the middle. Lift them to a rack, not a heap of paper towels, so the corners stay dry while you make the glaze.
- 5
Cook the syrup
Put the sugar and 2 tablespoons water in a wide skillet. Stir only until the sugar is evenly wet, then bring it to a boil over medium heat and leave it alone. When the bubbles grow large, slow, and glossy, 3 to 4 minutes, add the soy sauce and swirl the pan. The syrup should fall from a spoon in a thick thread. Pull it before it turns dark; this is ame, a sugar glaze, not caramel.
Stirring once the syrup boils can make sugar crystals form on the sides of the pan. Swirl instead, and keep your spoon out until the potatoes go in. - 6
Glaze and finish
Add the hot fried sweet potatoes to the skillet and turn them gently until every angled face shines. Scatter in the black sesame and lift the pieces onto an oiled plate or parchment, leaving space between them as they cool. Hot potato meeting thick syrup is the detail that decides the dish: too thin and the glaze slides off, too cold and it clumps. Serve warm or at room temperature.
Chef Tips
- •Choose Japanese satsumaimo if you can: reddish-purple skin, pale yellow flesh, firm weight in the hand. Orange-fleshed sweet potatoes are wetter and will soften more quickly. They are edible, of course, but the dish loses the chestnut-like texture that makes daigakuimo itself.
- •Do not peel the potatoes. The skin gives color, helps each piece hold together, and brings a faint earthy edge against the sugar. A peeled piece tastes flatter and looks as if it has misplaced its coat.
- •Hot sugar burns more fiercely than boiling water, so taste nothing from the pan until it has cooled on a spoon. Use a long-handled utensil and keep the skillet steady while you toss.
- •For a picnic, cool the glazed pieces in a single layer before packing. If you pile them while warm, they glue themselves into one grand potato, amusing once and inconvenient after that.
Advance Preparation
- •The sweet potatoes can be cut and soaked up to 30 minutes ahead. Drain and dry them completely before frying, or the oil will protest.
- •Fry the potatoes up to 1 hour ahead and leave them uncovered on a rack. Warm them briefly in 180 C / 355 F oil for 30 seconds before glazing if you want the corners crisp again.
- •Finished daigakuimo is best the day it is made. For a picnic, cool it fully and pack it in a shallow container lined with parchment.
Frequently Asked Questions
Nutrition Information
1 serving (about 160g)
Calories
390 calories
Total Fat
12 g
Saturated Fat
1 g
Trans Fat
0 g
Unsaturated Fat
11 g
Cholesterol
0 mg
Sodium
160 mg
Total Carbohydrates
68 g
Dietary Fiber
4 g
Sugars
28 g
Protein
2 g
Where cooking meets culture.
Culinary guides, cultural storytelling, and the editorial depth that makes cooking meaningful.
Discover Culinary ExplorerMore from Vegetable Nimono & Kinpira
Browse the full collection
Chef Takumi
Lemon-Simmered Japanese Sweet Potatoes (さつまいものレモン煮, Satsumaimo no Remon-ni)
Skin-on satsumaimo rounds, a little sugar, and thin lemon slices simmer into a bright side dish that keeps its shape and tastes even better after resting.
Chef Takumi
Lotus Root Kinpira (れんこんのきんぴら, Renkon no Kinpira)
Lotus root is all clean cut and crisp bite here: thin coins warmed in sesame oil, glossed with soy and sweetness, and finished before the snap has a chance to leave.
Chef Takumi
Miso-Glazed Eggplant (なす田楽, Nasu Dengaku)
Summer eggplant does most of the work here: tender slabs, a sweet aka-miso glaze, a brief spell under fierce heat, and sesame for the small crackle at the end.