Description
A flavorful and hearty Portobello Romesco Burger featuring marinated and sautéed portobello mushroom caps topped with melted provolone cheese, caramelized red onions, and a bright, tangy homemade romesco sauce. Served on toasted buns with fresh microgreens or arugula and a spread of hummus or mayonnaise for a satisfying vegetarian burger experience.
Ingredients
Portobello Burgers
- 4 large portobello mushroom caps, wiped clean and stems removed
- 1/3 cup balsamic vinegar
- 3 tbsp extra-virgin olive oil
- 1 tbsp Italian seasoning
- 1/2 tsp garlic powder
- 1/2 tsp kosher salt
- 1/2 tsp black pepper
- 1 medium red onion, peeled and thinly sliced
- 4 slices provolone cheese (or sliced cheese of choice)
- 4 buns of choice, toasted
- Microgreens or fresh arugula for garnish
- Hummus or mayonnaise for topping
Romesco Sauce
- 1 (12-oz.) jar roasted red peppers, drained
- 1/3 cup sliced almonds (substitute pine nuts or chopped walnuts if desired)
- 1/4 cup oil-packed sun-dried tomatoes, drained
- 2 tbsp extra-virgin olive oil
- 1 tbsp red wine vinegar
- 1 clove garlic
- 1/2 tsp smoked paprika
- 1/2 tsp kosher salt
- 1/2 tsp black pepper
Instructions
- Marinate Mushrooms: Place the portobello mushroom caps in a 9×13-inch baking dish. In a medium bowl, whisk together 3 tablespoons olive oil, balsamic vinegar, Italian seasoning, garlic powder, kosher salt, and black pepper. Pour the marinade over the mushrooms. Using a pastry brush, coat both sides of each mushroom, flipping gently and finishing with the stem side up. Let the mushrooms marinate uncovered at room temperature for at least 30 minutes or up to 2 hours to absorb the flavors.
- Prepare Romesco Sauce: Combine roasted red peppers, sliced almonds, sun-dried tomatoes, extra virgin olive oil, red wine vinegar, garlic, smoked paprika, kosher salt, and black pepper in a blender or food processor. Blend until the sauce is mostly smooth but still has some texture. Set aside at room temperature.
- Sauté Red Onion: Heat 1 to 2 tablespoons olive oil in a large skillet over medium heat. Add the thinly sliced red onion and a pinch of salt. Cook, stirring occasionally, until the onions are soft and lightly caramelized with slightly crisp edges, about 8 to 10 minutes. Transfer the onions to a bowl and set aside.
- Cook Mushrooms: Wipe out the skillet if necessary and return to medium heat. Add the marinated portobello mushrooms and sauté for 4 to 5 minutes on each side, until they are deeply golden brown on the edges and have reduced in size. While cooking, brush the mushrooms with any leftover marinade to enhance flavor. Place a slice of provolone cheese on each mushroom and cover the skillet with a lid. Cook for an additional minute until the cheese melts.
- Assemble Burgers: Lightly toast the buns. Spread a generous amount of romesco sauce on the bottom half of each bun and a swipe of hummus or mayonnaise on the top half. Layer the bottom bun with one cooked portobello mushroom cap, caramelized onions, and a handful of microgreens or fresh arugula. Place the top bun on and serve immediately for a delicious vegetarian burger.
Notes
- Marinating the mushrooms for longer (up to 2 hours) intensifies the flavor.
- If you prefer a nut-free romesco, omit the almonds and add more roasted red peppers or sunflower seeds.
- Substitute provolone cheese with vegan cheese to make this dish vegan-friendly.
- Use gluten-free buns to accommodate gluten sensitivities.
- Romesco sauce can be made ahead and refrigerated for up to 3 days.
- Prep Time: 30 minutes
- Cook Time: 30 minutes
- Category: Burger
- Method: Stovetop
- Cuisine: American
