Half roast chicken with creamy tarragon & wild mushroom sauce

Ingredients

• 650g Field & Flower Lemon, Garlic & Thyme Half Roast Chicken
• 1 tbsp olive oil
• Knob of butter
• 3 large shallots, diced
• 1 large clove of garlic, crushed
• 200g wild mushrooms, sliced in half if large
• 2 tbsp chopped tarragon, plus extra to serve
• 1 small glass of white wine
• 150ml double cream
• Sea salt & freshly cracked black pepper