Portobello Burgers With Pesto And Roasted Red Peppers Recipe

Name: Portobello Burgers With Pesto And Roasted Red Peppers Recipe
Ingredients: * 1/2 cup purchased pesto; * 1/4 cup mayonnaise; * 4 sourdough, whole grain, onion, or ciabatta rolls, split horizontally; * 4 portobello mushrooms, stemmed, dark gills scraped out; * olive oil; * 4 slices provolone; * roasted red peppers from jar, drained; * 4 cups arugula or spinach (about 2 ounces)