Classic Chicken Marsala with Creamy Mushroom Sauce

Ingredients

• 1 1/2 pounds boneless skinless chicken breasts, pounded 1/4-inch thick
• 3 tablespoons all-purpose flour
• 3/4 teaspoon salt, plus more to taste
• 1/4 teaspoon freshly ground black pepper
• 1 tablespoon olive oil
• 3 tablespoons unsalted butter, divided
• 1 (8-ounce) package pre-sliced bella or button mushrooms
• 3 tablespoons finely chopped shallots (from 1 medium shallot)
• 2 cloves garlic, minced
• 2/3 cup chicken broth
• 2/3 cup dry Marsala wine
• 2/3 cup heavy cream
• 2 teaspoons chopped fresh thyme
• 2 tablespoons chopped fresh Italian parsley (optional, for garnish)