Japanese Yellowtail with Ginger Roasted Shiitake Mushrooms and Root Beer Hoisin Vinaigrette

Name: Japanese Yellowtail with Ginger Roasted Shiitake Mushrooms and Root Beer Hoisin Vinaigrette
Ingredients: 16 shiitake mushrooms, stems removed; 2 tablespoons olive oil; 1-ounce fresh ginger, peeled and sliced thinly; Salt; 2 tablespoons soy sauce; 1/4 cup root beer, flat; 1 tablespoon hoisin; 2 tablespoons white balsamic vinegar; 1 tablespoon mirin, boiled 10 seconds and cooled; 1 teaspoon minced shallots; 1/2 cup peanut oil; 4 (5-ounce) Japanese yellowtail fillets; 2 tablespoons peanut oil; Salt and pepper