chicken cutlets with tarragon-mushroom sauce

Ingredients For chicken cutlets with tarragon-mushroom sauce

• 2 c

  unsalted chicken stock
• 1/2

  carrot, cut into 1 inch pieces
• 1/2

  celery stalk, cut into 1-inch pieces
• 1/4

  onion, halved
• 1

  bay leaf
• 1 clove

  garlic, crushed
• 4``

  skinless, boneless chicken breast halves, 6 ounces each
• 1/2 tsp

  kosher salt, divided
• 1/2 tsp

  black pepper, divided
• 3 Tbsp

  all-purpose flour
• 2 Tbsp

  olive oil, divided
• 2 tsp

  butter, divided
• 1 c

  mushrooms, quartered
• 1/2 c

  green onion, sliced
• 1 Tbsp

  water
• 2 1/2 tsp

  cornstarch
• 1 Tbsp

  fresh tarragon, chopped