Preheat oven to 450 degrees F. Coat baking sheet with nonstick olive-oil-flavored cooking spray.
Heat butter and 1 tablespoon oil in large skillet over medium heat. Add shallots, garlic and basil; sauté for 3 minutes. Add mushrooms; cook, stirring occasionally, 10 minutes. Stir in balsamic vinegar, salt and pepper.
Place bread slices on prepared baking sheet. Brush top side of each slice with remaining olive oil. Top each slice with mushroom mixture. Sprinkle with Parmesan.
Bake in 450 degree F oven for 15 minutes or until heated through and the cheese is melted. Makes 8 servings.