Mushroom Grilled Cheese

Ingredients

• 1 tablespoon butter
• 1 tablespoon olive oil
• 1 small onion, sliced
• 8 ounces cremini mushrooms, sliced
• 2 cloves garlic, chopped
• 1 teaspoon thyme, chopped
• 1/4 cup white wine or broth
• salt and pepper to taste
• 1 tablespoon parsley, chopped
• 1/2 teaspoon truffle oil (optional)
• 1 cup fontina or gruyere, shredded
• 1/4 cup parmigiano reggiano, grated
• 4 slices bread
• 2 tablespoons butter