Slow-Cooked Chicken with Herbed Biscuits

INGREDIENTS

• 2 lb. boneless, skinless chicken breasts, cut into 1-inch cubes
• Kosher salt and freshly ground pepper, to taste
• 2 Tbs. canola oil
• 3/4 lb. chanterelle mushrooms, cleaned and quartered
• 16 Tbs. (2 sticks) unsalted butter, cut into 1/2-inch cubes
• 1 cup all-purpose flour
• 1/3 cup dry sherry
• 1 Tbs. chicken demi-glace
• 5 cups chicken stock
• 2 tsp. chopped fresh thyme
• 1 1/2 cups pearl onions
• 3 celery stalks, sliced
• 5 carrots, sliced
• 1 lb. red potatoes, cut into 1/2-inch dice
• 2 cups all-purpose flour, plus more as needed
• 1 Tbs. baking powder
• 1 1/2 tsp. kosher salt
• 2 tsp. sugar
• 8 Tbs. (1 stick) cold unsalted butter, cut into 8 pieces
• 1 cup grated Parmigiano-Reggiano cheese
• 1/4 cup chopped fresh chives
• 2 Tbs. chopped fresh flat-leaf parsley
• 3/4 cup plus 2 Tbs. buttermilk
• 1 1/2 cups fresh or frozen peas
• 1/4 cup chopped fresh flat-leaf parsley
• 2 Tbs. unsalted butter, melted