Chef Takumi
Agar Jelly with Anko and Fruit (あんみつ, Anmitsu)
Anmitsu looks like a tray of small tasks, but the work is calm: dissolve the kanten fully, chill the pieces clean, then let fruit, anko, and kuromitsu do the speaking.
Culinary Explorer
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Sweet Potato Yōkan (芋羊羹, Imo Yōkan)
Created by
Imo yōkan is Asakusa's quiet autumn sweet: steamed satsumaimo, sugar, and a pinch of salt, pressed into a clean block and left to set by the potato's own starch.
Desserts
Japanese
Comfort Food
Make Ahead
Special Occasion
20 min
Active Time
35 min cook•2 hr 55 min total
Yield1 loaf, about 8 slices
Agood satsumaimo needs very little help. When the sweet potato is in shun, at its prime, the flesh is yellow, dense, and sweet enough to make a confection without hiding itself behind bean paste or agar. This is the plainness I like. Nothing hidden.
Yōkan sounds like a difficult sweet because most people think of the glossy bean version set with kanten, or agar. Imo yōkan is simpler. Steam the potato until it gives up completely, mash it while warm with sugar and salt, then press it firmly into a mold. The potato's starch is the setting agent. The first secret is not an ingredient, but patience: steam it until soft all the way through, then press it while warm, before the starch cools and tightens.
The texture should be smooth but not slippery, a firm slice that breaks cleanly under the tooth and tastes first of sweet potato. We serve it in small pieces, often with tea, because wagashi is not meant to shout across the table. Cut three neat bars, leave them room on the plate, and let the color do its work. Honmono is sometimes only the ingredient allowed to stand upright.
Imo yōkan is closely tied to Asakusa in Tokyo, especially the confectioner Funawa, founded in 1902 during the Meiji period. Ordinary yōkan made from red bean paste and kanten was a more costly sweet, while sweet potatoes were familiar, filling, and widely available, so the potato itself became the body of the confection. The result kept the rectangular yōkan shape but changed the substance completely: no anko, no agar, just steamed satsumaimo pressed into form.
The technique, the tradition, and the story behind every dish.
Discover Culinary ExplorerIngredients
Japanese sweet potatoes (satsumaimo)
Quantity
700g
scrubbed
granulated sugar
Quantity
80g
fine sea salt
Quantity
1/4 teaspoon
mirin (optional)
Quantity
1 teaspoon
neutral oil
Quantity
a little
for the mold
| Ingredient | Quantity |
|---|---|
| Japanese sweet potatoes (satsumaimo)scrubbed | 700g |
| granulated sugar | 80g |
| fine sea salt | 1/4 teaspoon |
| mirin (optional) | 1 teaspoon |
| neutral oilfor the mold | a little |
Equipment Needed
- •Steamer basket or bamboo seiro
- •Potato ricer or fine sieve
- •Nagashikan rectangular mold, or a small parchment-lined loaf pan
- •Bench scraper or flat spatula
Instructions
- 1
Steam the potatoes
Set the sweet potatoes in a steamer and steam over steady heat for 30 to 35 minutes, until a skewer slides through the thickest part without resistance. Steaming keeps the flesh dense and sweet, while boiling can waterlog it and make the finished block slack. Let them cool only until you can handle them.
- 2
Peel while warm
Peel away the skins and trim off any fibrous or dark spots. Work while the potatoes are still warm. Warm starches mash smoothly and take in sugar evenly; cold potato fights back like a clerk at closing time.
If the potato smells earthy or has hard, woody fibers, don't force it into a sweet. Sourcing first. Imo yōkan has no sauce to cover a tired ingredient. - 3
Mash and season
Pass the warm potato through a ricer or mash it very thoroughly, then stir in the sugar, salt, and mirin if using. Taste before you press it. It should be gently sweet, with the salt only sharpening the potato, not announcing itself.
- 4
Smooth the paste
For the cleanest texture, press the mash through a fine sieve with a spatula. This is not fuss for its own sake. The sieve catches fibers and gives the finished yōkan its calm, even face when sliced.
- 5
Press into mold
Lightly oil a nagashikan, the rectangular Japanese mold used for set sweets, or line a small loaf pan with parchment. Pack the sweet potato paste in firmly, pressing into the corners and smoothing the top. Firm pressure removes air pockets, and air pockets make ragged slices.
- 6
Chill and slice
Cover the surface and refrigerate for at least 2 hours, until firm. Unmold, trim the edges if you like, and cut into small bars with a clean knife wiped between cuts. The slice should hold its shape, with a matte golden face and no crumbling.
Chef Tips
- •Use Japanese satsumaimo if you can: red-purple skin, pale yellow flesh, dense and chestnut-sweet when cooked. Orange American sweet potatoes are wetter and softer, and they make a different sweet. Pleasant, yes, but not this one.
- •Adjust the sugar to the potato, not to pride. A very sweet autumn satsumaimo may need less; a drier one may need the full amount. Taste while warm, because cold dulls sweetness.
- •A nagashikan gives the neat yōkan shape, but a small parchment-lined loaf pan works cleanly. The important part is pressure. Pack it firmly, or the slice will tell on you.
- •Serve it small, with sencha or hojicha. Three slices on a plate look calmer than a crowded row. Leave it room.
Advance Preparation
- •Imo yōkan is best made at least 2 hours ahead so the starch can firm and the block can slice cleanly.
- •Keep it covered in the refrigerator for up to 3 days. Slice only what you plan to serve, because cut faces dry faster.
- •Let the slices stand at cool room temperature for 10 minutes before serving. The flavor opens a little, and the texture softens without losing its shape.
Frequently Asked Questions
Nutrition Information
1 serving (about 95g)
Calories
160 calories
Total Fat
0 g
Saturated Fat
0 g
Trans Fat
0 g
Unsaturated Fat
0 g
Cholesterol
0 mg
Sodium
120 mg
Total Carbohydrates
38 g
Dietary Fiber
2 g
Sugars
15 g
Protein
1 g
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