Skillet Chicken Pot Pie with Cheddar Biscuits

Ingredients

• 6 tablespoons (3/4 stick) unsalted butter, divided
• 3 small or 2 large boneless skinless chicken breasts
• Salt and pepper
• 1 medium yellow onion, chopped
• 2 carrots, peeled and diced
• 8 oz. button or baby bella mushrooms, trimmed and chopped
• 2 cloves garlic, minced or pressed
• 1 teaspoon fresh thyme leaves
• 1/4 cup all-purpose flour
• 1 1/4 cups chicken broth
• 1 1/4 cups milk
• 1 cup frozen peas
• 1 1/2 cups all-purpose flour
• 1 1/2 teaspoons baking powder
• 1/2 teaspoons kosher salt
• 1/2 teaspoon dried parsley
• Dash of cayenne pepper
• 6 tablespoons (3/4 stick) unsalted butter, cold and cut into small pieces
• 1/2 cup plus 2 tablespoons buttermilk
• 2 ounces cheddar cheese, coarsely shredded