Grilled Portobello Mushroom Tacos Recipe

Name: Grilled Portobello Mushroom Tacos Recipe
Ingredients: 3 teaspoons champagne vinegar; 1 head garlic, roasted; 1/4 shallot, minced; 3 teaspoons white truffle oil; 1 cup mayonnaise; 6 large portobello mushrooms; 4 tablespoons olive oil; 1 red onion, sliced; 1 yellow onion, sliced; 1/4 cup olive oil; 1/2 teaspoon kosher salt; 1/2 teaspoon ground black pepper; 1 cup fresh orange juice; 12 (4-inch) corn tortillas; 6 large radishes, thinly sliced; 6 ounces Parmesan cheese, thinly sliced; 2 cups pea shoots