Japanese Vegetable Curry (Yasai Kare)

A rich, velvety curry built on kombu-shiitake dashi and a from-scratch butter roux — all the deep savory satisfaction of Japanese curry rice without meat. Snap peas and spinach go in at the end for color and crunch against the soft, stew-tender vegetables.

Why It Works

Japanese curry gets its signature thick, coating texture from a flour-butter roux — the same principle as a French bechamel, but loaded with curry spice. The roux emulsifies the fat into the broth, creating a silky sauce that clings to rice.

Umami without meat comes from stacking three sources: kombu (glutamates), dried shiitake (guanylate), and soy sauce (glutamates + fermented depth). Together these hit the same savory receptors as a beef-based curry. A spoonful of miso stirred in off-heat adds koku — that round, lingering richness.

Caramelized onions are the single most important flavor builder here. Cooking them low and slow for 15+ minutes converts their sugars, providing the subtle sweetness that defines Japanese curry (the same role that grated apple or honey plays in commercial curry blocks).

The snap peas and spinach are added in the final 2 minutes intentionally — they provide texture contrast (crisp-tender vs. soft stew) and a fresh, green brightness that keeps the dish from feeling heavy.

Ingredients

Roux and seasonings scale linearly. Simmer time stays the same regardless of batch size.

Dashi

• 4 cups (960 ml) water
• 1 piece kombu (about 4 inches / 10 cm)
• 4-5 dried shiitake mushrooms

Vegetables

• 2 large onions, thinly sliced
• 3 cloves garlic, minced
• 1 tbsp fresh ginger, grated
• 2 medium Yukon gold potatoes, cut into 1-inch chunks
• 2 medium carrots, roll-cut or oblique-cut into chunks
• 8 oz (225 g) cremini or fresh shiitake mushrooms, quartered
• 1 cup (100 g) snap peas, trimmed and halved on the bias
• 3 oz (85 g) baby spinach (about 2 large handfuls)

Roux

• 3 tbsp (45 g) unsalted butter
• 3 tbsp (25 g) all-purpose flour
• 2-3 tbsp S&B curry powder (adjust to taste)

Seasonings

• 2 tbsp (30 ml) soy sauce
• 1 tbsp white miso paste
• 1 tsp honey or sugar
• 1 tbsp ketchup (optional — adds a subtle tangy sweetness)
• Salt to taste

Serving

• Steamed short-grain rice
• Pickled ginger (beni shoga) or fukujinzuke if you have it

Instructions

1. Make the dashi. Combine water, kombu, and dried shiitake in a pot. Let it soak for at least 20 minutes (or while you prep vegetables). Bring to a gentle simmer over medium heat — pull the kombu out just before it boils. Let the shiitake simmer another 5 minutes, then remove, slice thinly, and reserve. You should have about 3.5 cups of dashi.

2. Caramelize the onions. In a heavy-bottomed pot or Dutch oven, melt 1 tbsp butter over medium heat. Add the sliced onions with a pinch of salt. Cook for 15-20 minutes, stirring occasionally, until deeply golden and sweet. Don’t rush this — it’s the flavor foundation.

3. Build the aromatics. Add garlic and ginger to the caramelized onions. Stir for 60 seconds until fragrant.

4. Add the hearty vegetables. Add potatoes, carrots, fresh mushrooms, and the reserved sliced shiitake. Stir to coat with the aromatics, cook 2-3 minutes.

5. Pour in the dashi. Add the dashi, soy sauce, honey, and ketchup if using. Bring to a boil, then reduce to a gentle simmer. Cover and cook for 15-18 minutes until potatoes and carrots are fork-tender.

6. Make the roux. While the vegetables simmer, melt 2 tbsp butter in a small saucepan over medium-low heat. Add the flour and stir constantly for 2-3 minutes until it smells nutty and turns a shade darker. Add the curry powder and stir another 30 seconds to bloom the spices in the fat. Ladle in about 1/2 cup of the hot dashi from the pot and whisk until smooth — this tempers the roux so it won’t clump.

7. Thicken the curry. Pour the tempered roux back into the main pot, stirring as you go. Simmer uncovered for 5-8 minutes, stirring occasionally, until the sauce is thick enough to coat the back of a spoon.

8. Finish with greens. Add the snap peas and cook 1 minute. Add the spinach and stir until just wilted, about 30 seconds. Remove from heat.

9. Season. Stir in the miso paste (dissolve it in a spoonful of sauce first so it incorporates smoothly). Taste and adjust with salt or more soy sauce as needed.

10. Serve. Spoon curry alongside steamed rice. Garnish with pickled ginger if you have it.

Variations & Substitutions

• Kabocha or sweet potato in place of Yukon gold — adds natural sweetness and melts into the sauce slightly
• Broccoli florets instead of snap peas — add in step 8
• Eggplant — cube and add with the hearty vegetables in step 4; it will break down and thicken the sauce further
• Coconut oil instead of butter for a vegan version; sub maple syrup for honey and skip the miso or use a vegan miso
• Spice level — S&B is mild; for more heat, add 1/2 tsp cayenne to the roux or serve with shichimi togarashi
• Extra umami — a splash of Worcestershire sauce (check if vegetarian) or a grated tomato added with the dashi
• Curry blocks — if you want a shortcut, skip the roux and use 1/2 box of Golden Curry or Vermont Curry blocks instead (just break them into the simmering broth)

Notes from Testing

• Not yet tested — this is a WIP recipe. Will update after first cook.