Christmas Grouse with Berry Sauce (Jólarjúpa með Berjasósu)

Ingredients

• 4 (8-oz.) grouse or partridge
• 2 tbsp. olive oil
• 1 carrot, roughly chopped
• 8 cups chicken stock
• 1 ¹⁄₂ cups dried blueberries
• 1 ¹⁄₂ cups fresh blueberries
• 1 ¹⁄₄ tsp. dried thyme
• 2 bay leaves
• 3 ¹⁄₄ cups heavy cream
• 4 tbsp. unsalted butter, cubed and chilled
• Kosher salt and freshly ground black pepper, to taste