Cast-Iron Grilled Portobello Mushroom Steaks with Garlic-Parsley Butter

By AislePrompt Editorial · ·

How this recipe was made — this recipe was drafted by AislePrompt's AI-assisted pipeline from technique templates and USDA-sourced nutrition data, and published by AislePrompt Editorial — see how AislePrompt recipes are developed and reviewed.

Meaty portobello mushrooms seared on a cast-iron grill pan, topped with a fragrant garlic-parsley butter that melts into every crevice. This Mediterranean-inspired vegetarian recipe, ready in about 25 minutes, pairs large portobello mushroom caps, olive oil, unsalted butter for a weeknight-friendly dinner that comes together with one pan and minimal cleanup. Each serving lands at about 180 calories and feeds 4, so it slots cleanly into a weekly meal plan and pairs well with a quick salad or grain on the side. Tap "Plan a meal with the AI" below to drop this recipe into your week and send the ingredients straight to Instacart. Nutrition values are approximate, calculated from USDA FoodData Central (fdc.nal.usda.gov) — verify against ingredient labels for any health-driven dietary plan.

Prep: 10 min Cook: 15 min Serves 4 Mediterranean cuisine 180 cal/serving
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Ingredients

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Instructions

  1. Step 1: Clean 4 large portobello mushroom caps by wiping with a damp cloth and removing the stems. Brush both sides with 3 tablespoons olive oil and season evenly with 1 teaspoon salt and 1/2 teaspoon black pepper.
  2. Step 2: Heat a cast-iron grill pan over medium-high heat until smoking hot, about 5 minutes. Place the mushrooms gill-side down on the pan and grill for 5 minutes until grill marks form and mushrooms start to soften.
  3. Step 3: Flip the mushrooms and grill for an additional 4 minutes. Meanwhile, melt 4 tablespoons unsalted butter in a small saucepan over low heat. Add 3 minced garlic cloves and 2 tablespoons finely chopped fresh parsley, cooking gently for 2 minutes until fragrant without browning.
  4. Step 4: Remove the mushrooms from the pan and drizzle with 1 tablespoon balsamic vinegar. Spoon the warm garlic-parsley butter generously over the mushrooms and serve immediately.

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