Portobello Mushroom Bruschetta with Garlic Aioli

 Portobello Mushroom Bruschetta with Garlic Aioli

1 1/2 cups balsamic vinegar

1/4 cup honey

1/4 cup brown sugar, packed 

1 1/2 tbsp fresh Thyme, Chopped 

6 - 4” portobello mushrooms, stemmed & dark gills removed 

3 tbsp olive oil

3 red onions, sliced (about 6 cups)

2 red peppers

3 tbsp green onion, thinly sliced 

3 tbsp fresh basil, chopped 

1 garlic clove, minced 

1 cup mayonnaise 

2 tbsp lemon juice 

2 garlic clove, minced 

1/2 tsp kosher salt 

2 French bread baguettes, cut into 24 slices 

Olive oil

5 oz arugula, coarsely chopped 

Balsamic glaze 

Preheat oven to 375 degrees. 

Mix vinegar, honey, brown sugar and thyme in a medium bowl. Transfer 1/2 cup marinade to a small bowl and set aside. Place mushrooms in a 9 x 13 glass baking dish. Pour remaining marinade over mushrooms. Cover with foil and bake until mushrooms are tender, about 40 minutes. Transfer mushrooms to work surface. Cool and cut into 1/2” slices. 

Heat oil in a large skillet over medium heat. Add red onions and sauté until very tender & beginning to brown, approximately 25 minutes. Pour in reserved marinade and cook until liquid is absorbed and onions are glazed, about 15 minutes. Set aside. 

Char red peppers over gas flame or under a broiler until blackened on all sides. Enclose in a paper bag and let stand 10 minutes. Peel, seed and chop peppers. Place peppers in a medium bowl, add green onion, basil, garlic and 1 tablespoon oil & toss to combine. 

Mushrooms, onion mixture and red pepper mixture can be prepared 1 day ahead, cover separately and refrigerate. 

In a small mixing bowl combine mayonnaise, lemon juice, garlic and kosher salt. Cover and refrigerate until needed. 

Preheat oven to 375 degrees   Place bread slices on a baking sheet. Brush with additional olive oil. Bake until lightly toasted, approximately 10 minutes. Layer portobello mushroom slices, arugula, onions and red pepper mixture on bread slices. Bake until heated through, about 3 minutes. 

Transfer bruschetta to a serving plate. Add dollops of garlic Aioli for dipping, drizzle with balsamic glaze and serve.