Chicken and mushroom pot pies

Method

1. Bring the stock, peppercorns, thyme and bay to a simmer in a medium pan. Add the chicken, turn down to a gentle simmer and poach for 15-20 mins until tender.
2. Meanwhile, fry the mushrooms in the oil for 2 mins, then add the shallots and garlic and cook for 3-4 mins until soft. Take off the heat, stir in the artichokes and set aside.
3. Lift the chicken onto a tray and strain the stock. Let both cool slightly.
4. Melt the butter in a pan, stir in the flour and cook for 2 mins. Gradually whisk in the strained stock over a medium heat until thickened, then stir in both mustards, the tarragon, crème fraîche, sherry vinegar and the mushroom mix.
5. Cut the chicken into bite-sized pieces and fold into the sauce. Season, cool slightly, then divide between 4 individual pie dishes and chill.
6. Roll the pastry on a floured surface to 5mm thick and cut 4 rounds 2cm wider than the dishes. Brush the edges with egg, lay a round egg-side down over each dish, brush the tops with egg and chill for 20 mins.
7. Heat the oven to 200C/180C fan/gas 6. Cut a couple of slits in each lid and bake for 30 mins until crisp and deep golden. Rest for a few mins before serving.