
Portobellos Stuffed with Creamy Rosemary Polenta, Balsamic Lentils and Olive Gremolata
An original dairy-free recipe of roasted portobello mushrooms filled with silky rosemary polenta, topped with balsamic-glazed lentils and finished with a bright olive, lemon and parsley gremolata. Comforting, elegant, and fully plant-based.
Ingredients
- 4 4 units (approx. 520 g) large portobello mushrooms (without stalk, limpios)
- 5 75 ml olive oil (divided)
- 7 7 g sea salt (or to taste, divided)
- 2 2 g black pepper (divided)
- 4 4 cloves (16 g) garlic (2 chopped and 2 grated or muy finely chopped, divided)
- 400 400 g cooked lentils (escurridas si son of conserva)
- 120 120 g red onion (chopped fina)
- 30 30 ml balsamic vinegar
- 1 1 g dried thyme
- 150 150 g instant polenta (harina of maíz for polenta quick)
- 600 600 ml vegetable broth (low sodium preferiblemente)
- 240 240 ml unsweetened oat milk (without lácteos)
- 6 6 g fresh rosemary (divided)
- 20 20 g nutritional yeast
- 60 60 g green olives (boneless, chopped)
- 15 15 g fresh parsley
- 1 1 unit lemon (1 tbsp juice)
- 1 1 g red pepper flakes (optional)
Nutrition facts
per serving
Approximate nutritional information. Estimated from the recipe’s ingredients and amounts, using standard reference nutrition values. It may vary with brands, sizes and cooking method. For guidance only; not a substitute for medical or dietary advice.
Allergens
Instructions
- 1
Preheat the oven to 425°F / 220°C. Place the portobellos on a baking tray cavity side up. Rub them with 2 tablespoons olive oil, season with 1/2 teaspoon salt and 1/4 teaspoon black pepper, and distribute 2 grated garlic cloves over them. Roast for 18 to 20 minutes, until tender and slightly juicy.
- 2
While the portobellos roast, make the balsamic lentils. Heat 1 tablespoon olive oil in a medium skillet over medium heat. Add the red onion and cook for 4 to 5 minutes until softened. Stir in 2 minced garlic cloves and cook for 30 seconds. Add the cooked lentils, balsamic vinegar, dried thyme, 1/4 teaspoon salt, and 1/4 teaspoon black pepper. Cook for 5 to 7 minutes, stirring, until the lentils are glossy and well seasoned.
- 3
For the polenta, bring the vegetable broth and oat milk to a gentle boil in a medium saucepan. Gradually whisk in the instant polenta to prevent lumps. Lower the heat and cook for 4 to 5 minutes, stirring often, until thickened. Stir in 1 tablespoon olive oil, the nutritional yeast, 1 tablespoon chopped fresh rosemary, and 1/4 teaspoon salt. Mix until creamy.
- 4
Make the gremolata by combining the green olives, fresh parsley, lemon zest, 1 tablespoon lemon juice, the remaining 1 tablespoon olive oil, the remaining 1 tablespoon chopped fresh rosemary, and the red pepper flakes if using in a small bowl.
- 5
When the portobellos are ready, carefully pour the liquid from the tray into the lentil skillet to deepen the flavor. Cook the lentils for 1 more minute to combine.
- 6
Fill each portobello with a generous layer of creamy polenta. Spoon the balsamic lentils on top and finish with the olive gremolata.
- 7
Serve immediately while warm, with extra tray juices spooned over the top if desired.
Chef tips
If the polenta thickens too much before serving, add 2 to 4 tablespoons of hot broth or water and whisk until smooth again. Pat the portobellos dry before roasting so they roast instead of steam.
Substitutions
You can use medium portobello mushrooms and make 6 lighter servings. Oat milk can be replaced with soy milk if soy is not an issue. Green olives can be swapped for black olives for a deeper flavor.
What I used to make it
Generic kitchen tools that work for this recipe. You don’t need to buy anything to make it.
Illustrative imageCosori Pro LE 5 Qt Air Fryer
Browning and baking with little oil
- Browns food with very little oil
- Handy for vegetables, chicken and reheating
- Check the basket capacity
Illustrative imageT-fal Ultimate Hard Anodized 12" Non-Stick Pan
Eggs, omelets and stir-fries
- Eggs and omelets that don’t stick
- Comfortable, sturdy handle
- Use wooden or silicone utensils
Illustrative imageVictorinox Fibrox Pro 8" Chef’s Knife
Chopping, slicing and cutting strips
- The knife I use most when cooking
- Chops, slices and cuts into strips
- Keep it sharp and hand-dry it
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