# Sous Vide Tuna with Hedgehog Mushrooms, Brussels Chips, and Root Vegetable Fries > Gently cooked tuna gets a generous topping of golden hedgehog mushrooms, sweet shallots, and fresh parsley. Crisp Brussels leaves and roasted parsnip–sweet potato fries bring browned edges and winter sweetness, with a little lemon keeping the plate bright. - URL: https://www.chezjk.com/recipes/sous-vide-tuna-loin-with-hedgehog-mushrooms-shallots-brussels-chips-parsnip-swee - Author: Jonathan Katzman - Cooked and photographed: 2022-01-12 - Recipe updated: 2026-10-23 - Serves: 4 servings - Tags: gluten-free, paleo, nut-free, pescatarian ![Sous Vide Tuna with Hedgehog Mushrooms, Brussels Chips, and Root Vegetable Fries](https://www.chezjk.com/api/images?path=9e5d6860-dd86-455e-b57b-e352c363fc57%2Fe595da19316df85b.jpg) ## Sous Vide Tuna Loin A controlled water bath keeps lean tuna moist and evenly cooked. Leaving it unseared preserves its delicate texture beneath the warm mushroom topping. ### Ingredients - 1½ lb albacore tuna loin, cut into 4 portions about 1–1¼ inches thick - 1 tbsp extra-virgin olive oil - ¾ tsp Diamond Crystal kosher salt, or less fine salt - ¼ tsp freshly ground black pepper ### Instructions 1. Heat a sous vide bath to 130°F / 54.5°C. 2. Pat the tuna dry and season with salt and pepper. Place in a cooking bag with the olive oil, arranging the portions in a single layer. Seal gently without compressing the fish. 3. Submerge completely and cook for 45 minutes for 1-inch-thick portions or 60 minutes for 1¼-inch-thick portions. The tuna should be gently set, moist, and pale pink to ivory rather than deeply rosy. 4. Remove from the bag just before serving. Drain and blot gently, then transfer directly to plates without searing. ### Notes - This low-temperature treatment is not a pasteurization process. Use tuna from a trusted supplier suitable for undercooked service, with appropriate parasite controls where applicable. For pregnant, older, immunocompromised, or very young diners, cook fish to 145°F / 63°C instead. - Use thickness, not portion weight, to choose the cooking time; avoid a prolonged hold that can soften the tuna excessively. ## Hedgehog Mushrooms with Shallots and Parsley Browning the mushrooms before adding shallots builds savory depth without steaming them. Parsley and lemon lighten the buttery mushroom juices that dress the tuna. ### Ingredients - 12 oz hedgehog mushrooms - 2 medium shallots, sliced into thin half-moons - 2 tbsp ghee, divided - ¾ cup loosely packed flat-leaf parsley leaves, roughly torn - 2 tsp fresh lemon juice, plus more to taste - ¼ tsp kosher salt, plus more to taste - to taste freshly ground black pepper ### Instructions 1. Trim the mushrooms and brush away debris. Rinse briefly only if necessary and dry thoroughly. Leave small mushrooms whole and tear larger ones into bite-size pieces. 2. Heat a wide skillet over medium-high heat. Add 1 tablespoon ghee, then the mushrooms in a loose layer. Cook for 6–8 minutes, turning occasionally, until released moisture evaporates and golden patches develop; work in batches if crowded. 3. Reduce the heat to medium. Add the remaining ghee, shallots, and salt. Cook for 5–7 minutes, stirring, until the shallots are soft and lightly golden. 4. Remove from the heat and fold in the parsley, lemon juice, and pepper. Taste for salt and acidity. Spoon over the tuna while warm. ### Notes - If the pan is dry, loosen the mushroom juices with 1–2 tablespoons water before adding the parsley. Aim for a glossy topping, not a pooled sauce. ## Roasted Brussels Sprout Chips Separated leaves roast quickly into crisp, browned cups with tender green centers. Dry leaves and an uncrowded pan are more important than extra oil. ### Ingredients - 1 lb large Brussels sprouts - 1½ tbsp olive oil - ¼ tsp kosher salt - 1 tsp finely grated lemon zest ### Instructions 1. Heat the oven to 425°F / 220°C. Trim the Brussels sprout stems and peel off the leaves, trimming the base again as needed. Reserve the tight centers for another meal. 2. Dry the leaves thoroughly. Toss with olive oil and salt, then spread loosely over a large sheet pan, using a second pan if needed. 3. Roast for 8–14 minutes, checking after 6 minutes. Turn the leaves once and remove browned, crisp leaves as they finish so they do not burn. 4. Scatter with lemon zest and serve immediately, leaving uncovered to preserve their crisp edges. ### Notes - The finished leaves should have browned edges with some green remaining; uniformly dark leaves will taste bitter. ## Parsnip and Sweet Potato Fries Evenly cut batons roast into sweet, tender fries with browned edges. Separate pans let each root finish at its own pace and prevent crowding. ### Ingredients - 1 lb orange sweet potatoes, scrubbed - 1 lb parsnips, peeled - 2½ tbsp olive oil - ¾ tsp kosher salt - ¼ tsp freshly ground black pepper ### Instructions 1. Heat the oven to 425°F / 220°C. Cut both roots into roughly ⅜-inch-thick batons. Remove any woody core from large parsnips. 2. Toss with olive oil, salt, and pepper. Arrange the sweet potatoes and parsnips on separate sheet pans in single layers with space between pieces. 3. Roast for 30–40 minutes, turning after 20 minutes and rotating the pans. Begin checking the parsnips at 25 minutes; remove either vegetable when tender through the center and browned along the edges. 4. Combine just before serving and adjust the salt. ### Notes - These are browned oven fries with tender centers, not uniformly crunchy deep-fried fries. Avoid overcrowding or they will steam. ## Overall Timing / Workflow The tuna cooks hands-off while the roots roast. Mushrooms finish near serving time, and the delicate Brussels chips go into the oven last. ### Instructions 1. 0:00 — Heat the sous vide bath and oven. Prepare and bag the tuna, then start its thickness-appropriate cooking time once the bath is ready. 2. 0:10 — Cut and season the root vegetables; put them in the oven. Clean the mushrooms, slice the shallots, and separate and dry the Brussels leaves. 3. 0:30 — Turn the fries and rotate their pans. Start the mushroom sauté. 4. 0:40 — Check the roots and remove them as they finish. Roast the Brussels leaves on the freed oven rack, checking frequently. 5. 0:50–1:00 — Finish the mushrooms with parsley and lemon. Drain the tuna and plate with the hot vegetables and crisp leaves. ### Notes - If the roots finish early, leave them uncovered and return them to the oven for 2–3 minutes before serving. Do not cover the Brussels chips. ## Plating Keeping the crisp vegetables beside the tuna prevents mushroom juices from softening them. ### Instructions 1. Place one tuna portion toward the front of each warm plate. 2. Spoon the mushrooms, shallots, parsley, and a little pan juice generously over the tuna. 3. Arrange Brussels chips to one side and a loose stack of parsnip and sweet potato fries behind the fish. Serve immediately. ## Leftover Path Separate storage preserves the vegetables better, while gentle handling keeps the lean tuna from drying out. ### Instructions 1. Refrigerate leftovers promptly within 2 hours in separate shallow containers. Eat the low-temperature-cooked tuna within 24 hours; use the vegetables within 3 days. 2. Flake the chilled tuna over a lemon-dressed salad with leftover mushrooms, keeping it cold until serving. 3. Reheat fries at 425°F / 220°C for 5–10 minutes. Re-crisp Brussels leaves briefly, checking after 2 minutes; they will be more delicate than freshly roasted. ### Notes - Refrigeration does not make undercooked tuna suitable for high-risk diners; use fish cooked to 145°F / 63°C for those diners. --- From ChezJK (https://www.chezjk.com), Jonathan Katzman's public home-cooking archive: every meal he has photographed, written up as a recipe you can cook.