Grilled Portobello Sandwich with Roasted Red Pepper and Basil
Marinated portobello mushrooms are grilled until tender, then layered with roasted red pepper, arugula, and a creamy basil–white bean spread on toasted rolls. Fresh mozzarella is optional—the sandwich is flavorful and satisfying without it.
Serves: 4 | Prep Time: 20 minutes | Marinating Time: 20 minutes | Cook Time: 15 minutes | Total Time: 55 minutes
Why You’ll Love This Recipe
Portobello mushrooms make this vegetarian sandwich hearty and satisfying.
Roasted red peppers add sweetness, color, and smoky flavor.
The basil–white bean spread is creamy without mayonnaise or cheese.
The mushrooms can be cooked outdoors or on an indoor grill pan.
Ingredients
For the Portobello Mushrooms
4 large portobello mushroom caps
3 tablespoons olive oil
1½ tablespoons balsamic vinegar
2 garlic cloves, finely minced
1 teaspoon chopped fresh thyme, or ¼ teaspoon dried thyme
½ teaspoon freshly ground black pepper
For the Basil–White Bean Spread
¾ cup drained and rinsed No Salt Added cannellini beans
½ cup loosely packed fresh basil leaves
1 tablespoon freshly squeezed lemon juice
1 tablespoon olive oil
1 small garlic clove, roughly chopped
2–3 tablespoons water, as needed
¼ teaspoon freshly ground black pepper
For Assembly
4 Soft Hamburger Rolls or appropriately lower-sodium sandwich rolls
1 large roasted red bell pepper, drained, patted dry, and cut into wide strips
2 cups baby arugula
4 ounces fresh mozzarella, thinly sliced, optional
Equipment
Shallow dish
Small food processor or blender
Outdoor grill or indoor grill pan
Tongs
Instructions
1. Marinate the Mushrooms
Wipe the mushroom caps clean with a slightly damp kitchen towel. Remove the stems and, if desired, use a spoon to gently scrape away the dark gills. Place the mushrooms in a shallow dish.
Whisk together the olive oil, balsamic vinegar, garlic, thyme, and black pepper. Brush the marinade over both sides of the mushrooms. Let stand at room temperature for 20 minutes, turning once.
2. Make the Basil–White Bean Spread
Combine the cannellini beans, basil, lemon juice, olive oil, garlic, and black pepper in a small food processor or blender. Process until creamy, adding water 1 tablespoon at a time until smooth and easily spreadable. Set aside.
3. Grill the Mushrooms
Preheat an outdoor grill or indoor grill pan to medium-high heat.
Remove the mushrooms from the marinade, allowing the excess to drip back into the dish. Grill rounded-side down for 4–5 minutes. Turn and cook for another 4–6 minutes, or until browned and tender. Cover during the final few minutes if the mushrooms are especially thick.
Transfer to a cutting board and let rest for 3 minutes.
4. Toast the Rolls
Place the rolls cut-side down on the grill and toast for 1–2 minutes, or until lightly golden.
5. Assemble the Sandwiches
Spread the basil–white bean mixture over both cut sides of each roll. Place one mushroom on each bottom half, slicing particularly large mushrooms if necessary.
Top with roasted red pepper, optional mozzarella, and arugula. Add the top halves of the rolls and serve immediately.
Cook’s Note
Choose firm, dry portobello caps approximately the same diameter as the rolls.
Removing the gills is optional, but it prevents excess dark liquid and gives the sandwich a cleaner appearance.
Do not marinate the mushrooms for longer than 30 minutes or they may become overly soft.
Commercial sandwich rolls can contain considerable sodium. Use our homemade Soft Hamburger Rolls or compare labels and choose the lowest-sodium option available. Check the labels on roasted peppers and optional mozzarella as well; homemade roasted peppers are an excellent alternative.
Make Ahead
The basil–white bean spread can be refrigerated in an airtight container for up to 2 days. Roasted peppers can be prepared, peeled, and sliced up to 3 days ahead. For the best texture, grill the mushrooms and assemble the sandwiches shortly before serving.
Storage
Refrigerate the mushrooms, spread, peppers, and arugula separately for up to 3 days. Reheat the mushrooms in a covered skillet over medium-low heat or in a 350°F oven, then assemble the sandwiches. Freezing is not recommended.
Complete the Meal
Serve these Grilled Portobello Sandwiches with our Quick Pickled Cucumber Salad for a cool, crisp summer meal.