Jul 14 2026
RestaurantsOstraPortobello Mushroom Gratin Recipe

Portobello Mushroom Gratin Recipe

Inspired by Ostra
Time45m
Serves4

Feta cheese, grain salad, rocket, tomatillo sauce.

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Ingredients

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Ingredients

Method

Directions

  1. 1

    Prepare the Portobello Mushrooms

    Preheat the oven to 375°F (190°C). Clean the Portobello mushrooms and remove the stems. Place them on a baking sheet, gill side up.

  2. 2

    Make the Filling

    In a bowl, mix the cooked grain salad, feta cheese (crumbled), minced garlic, olive oil, salt, black pepper, and fresh herbs until well combined.

  3. 3

    Stuff the Mushrooms

    Spoon the filling mixture into each Portobello mushroom cap, pressing down gently to pack it in.

  4. 4

    Bake the Mushrooms

    Bake the stuffed mushrooms in the preheated oven for 25-30 minutes, or until the mushrooms are tender and the filling is slightly golden.

  5. 5

    Serve with Rocket and Tomatillo Sauce

    On a serving plate, place a handful of rocket and drizzle with tomatillo sauce. Top with the baked Portobello mushroom gratin and serve immediately.

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