Japanese-Style Poached Trout with Nameko, Komatsuna and Miso-Butter Kabocha

Gently poached trout sits over tender komatsuna with glossy nameko mushrooms and a light ginger-dashi broth. Alongside, red kabocha gets a deeply browned miso-butter glaze—sweet, salty and rich against the clean fish and greens. It's a quiet autumn dinner with plenty of umami and just enough acidity to keep everything bright.

By Jonathan Katzman · Cooked and photographed · Recipe updated

Serves: 4 servings

Tags: gluten-free, nut-free, pescatarian

Japanese-Style Poached Trout with Nameko, Komatsuna and Miso-Butter Kabocha

Ginger-Dashi Poached Trout

Barely simmering dashi gently cooks the trout without tightening its delicate flesh. Ginger and restrained tamari provide fragrance and depth while keeping the broth light.

Ingredients

  • 4 skinless trout fillets, 5–6 ounces each, pin bones removed
  • 4 cups unsalted kombu-bonito dashi, gluten-free
  • 1 inch fresh ginger, thinly sliced
  • 2 tsp gluten-free tamari
  • 2 tsp unseasoned rice vinegar
  • to taste fine sea salt
  • 2 tbsp finely chopped chives, for finishing

Instructions

  1. Lightly salt the trout and refrigerate while preparing the broth.
  2. Combine the dashi and ginger in a wide, shallow pan. Bring to a gentle simmer and infuse for 5 minutes. Stir in the tamari, then reserve 1/3 cup of this broth for the mushrooms and greens.
  3. Lower the heat until the remaining broth is steaming with only occasional tiny bubbles, approximately 175–185°F. Add the trout in one layer, with the broth reaching most of the way up the fillets.
  4. Cover loosely and poach for 6–10 minutes, depending on thickness, until the flesh flakes gently and the thickest part reaches 145°F. Do not let the liquid boil.
  5. Transfer the trout carefully to a warm plate. Remove the ginger from the broth, stir in the rice vinegar and adjust the salt. Keep the broth hot without further cooking the fish.
  6. Use the chives to finish the assembled bowls.

Notes

  • Choose a pan that holds the fillets snugly; an overly wide pan may require more dashi to reach the proper depth.
  • For homemade dashi, steep a 4-inch piece of kombu in 4 1/2 cups water for 30 minutes. Heat until almost simmering, remove the kombu, add 15 grams bonito flakes and turn off the heat. Steep 5 minutes and strain.

Nameko Mushrooms and Komatsuna Greens

Cooking the mushrooms first develops their savory flavor, while adding komatsuna stems before the leaves keeps the greens tender but lively. A little broth catches the mushroom juices and ties the vegetables to the fish.

Ingredients

  • 8 oz fresh nameko mushrooms, tough stem ends trimmed
  • 1 lb komatsuna, washed, stems and leaves separated and cut into 2-inch lengths
  • 1 tbsp avocado oil
  • 1/3 cup reserved ginger-dashi broth from the trout component
  • 1 tsp unseasoned rice vinegar
  • to taste fine sea salt

Instructions

  1. Gently clean the mushrooms, rinsing briefly only if needed, and drain well. Leave small mushrooms whole and halve any especially large ones lengthwise.
  2. Heat the avocado oil in a wide skillet over medium-high heat. Add the mushrooms and cook for 3–4 minutes, stirring occasionally, until glossy and lightly colored.
  3. Add the komatsuna stems and cook for 1 minute. Pour in the reserved broth, cover and cook for 1–2 minutes, until the stems are almost tender.
  4. Add the leaves and toss just until wilted, about 1 minute. Finish with rice vinegar and salt to taste. Serve promptly, retaining the small amount of cooking liquid.

Notes

  • If using packed nameko, drain them and follow any package cooking instructions; they will need less browning time than fresh mushrooms.
  • Keep the greens slightly firm, since hot broth will continue softening them in the bowl.

Miso-Butter-Glazed Red Kabocha

Roasting concentrates kabocha's sweetness and gives its edges structure. Applying the miso butter near the end creates a savory caramelized coating without burning the miso.

Ingredients

  • 1 small red kabocha squash, about 2 pounds, seeded
  • 1 tbsp olive oil
  • 3 tbsp unsalted butter, softened
  • 2 tbsp gluten-free white miso
  • 1 tsp honey
  • 2 tsp unseasoned rice vinegar
  • 1 tbsp finely chopped chives

Instructions

  1. Heat the oven to 425°F. Scrub the squash skin and cut the squash into wedges about 3/4 inch thick, leaving the edible skin on.
  2. Toss the wedges with olive oil and arrange in a single layer on a lightly oiled, broiler-safe sheet pan. Roast for 20 minutes, turn and roast for another 8–12 minutes, until tender with browned edges.
  3. Mash the softened butter with the miso, honey and rice vinegar into a spreadable glaze.
  4. Gently coat the hot squash with the glaze and return to the oven for 4–5 minutes. If needed, broil for 1–2 minutes until the coating bubbles and develops dark caramelized spots, watching constantly.
  5. Scatter with chives and serve hot, spooning any browned glaze from the pan over the wedges.

Notes

  • Miso varies in saltiness; taste the glaze before adding any extra salt.
  • If the squash is too firm to cut safely, microwave it whole for 2–3 minutes, let it cool briefly and then cut on a stable board.

Overall Timing / Workflow

The squash takes the longest and tolerates a short rest. Cooking the greens and trout near the end keeps their textures delicate and fresh.

Instructions

  1. 0:00 — Heat the oven to 425°F, cut the squash and begin roasting.
  2. 0:15 — Mix the miso-butter glaze, clean the mushrooms, cut the komatsuna and check the trout for pin bones.
  3. 0:25 — Turn the squash as needed. Infuse and season the dashi, reserving 1/3 cup for the vegetables.
  4. 0:30 — Start the mushrooms and komatsuna in a separate skillet. Begin gently poaching the trout.
  5. 0:35 — Glaze the tender squash and return it to the oven; broil briefly if needed.
  6. 0:40–0:45 — Check the trout for doneness, finish the broth with vinegar and assemble the bowls immediately.

Notes

  • If the squash needs longer, finish it before starting the trout; it can rest in a warm spot for 5–10 minutes.

Plating

A shallow bowl holds the delicate fish and broth, while keeping the squash alongside preserves its browned glaze.

Instructions

  1. Divide the komatsuna among four warm, shallow bowls, leaving a few stems visible around the edges.
  2. Set a trout fillet over each bed of greens and arrange the nameko around and over the fish.
  3. Ladle about 1/2 cup hot poaching broth around each fillet, rather than pouring directly over it. Finish with the reserved chives.
  4. Serve the miso-butter kabocha on small side plates or alongside the bowls on larger plates.

Leftover Path

Storing the broth separately prevents the fish and greens from becoming waterlogged. Gentle reheating protects the trout, while dry oven heat revives the squash.

Instructions

  1. Refrigerate the fish, broth, vegetables and squash in separate shallow containers within 2 hours. Use the fish, broth and greens within 2 days and the squash within 3–4 days.
  2. For a broth bowl, bring the reserved broth to a simmer, lower the heat and add the greens and flaked trout. Heat gently until the leftovers reach 165°F, without prolonged boiling.
  3. Reheat the squash in a 375°F oven for 10–15 minutes, loosely covering it if the miso glaze begins to darken too much.
  4. Alternatively, flake cold trout over freshly dressed greens and serve with the reheated squash.