Creamy Chicken & Tarragon Pie

Ingredients

• 800 g chicken thighs, boneless and cut into chunks
• 300 ml chicken stock
• 40 g plain flour
• 200 g mushrooms, quartered
• ½ tsp freshly ground black pepper
• 2 leeks, sliced (white and pale green parts)
• 2 garlic cloves, crushed
• 150 ml double cream
• 1 tsp sea salt
• 50 g unsalted butter
• 1 tbsp olive oil
• 1 tsp Dijon mustard
• 2 tbsp fresh tarragon, chopped
• 1 egg, beaten (for glazing)
• 375 g frozen puff pastry, thawed
• 15 g chives, finely snipped
• 450 g buttered peas and greens

Method

1. Heat the oven to 200°C (fan 180°C). Pat the chicken thoroughly dry, season generously with salt and pepper. Melt the butter with the olive oil in a large ovenproof frying pan over medium-high heat until it foams and the foam just starts to subside.
2. Brown the chicken in two batches, 2–3 minutes a side, until deeply golden. Don't crowd the pan; all at once and the pieces steam in their own juices instead of taking on colour, and that colour is what gives the dish depth. Lift each batch out and set aside.
3. Drop the leeks and mushrooms into the same pan with all those sticky brown bits and cook over medium heat for 6–8 minutes, stirring now and then, until the leeks are soft and silky and the mushrooms are glossy and catching at the edges. Stir in the crushed garlic and cook for just 30 seconds until fragrant; no more.
4. Scatter over the flour and stir for a full minute to cook out the raw, pasty edge. Pour in the chicken stock a splash at a time, stirring constantly so it stays smooth, then add the double cream. Keep stirring until the sauce thickens enough to coat the back of a spoon and the brown bits have lifted off the base into the sauce.
5. Return the chicken to the pan along with any resting juices. Stir in the Dijon and tarragon, then simmer gently for 3–4 minutes until the chicken is cooked through. Taste; the sauce should be silky, properly salted and richly herby.
6. Tip the hot filling into a deep 22–24cm pie dish. Roll the puff pastry out a touch larger than the dish, lay it over the top, trim the overhang and crimp the edges firmly against the rim; a loose seal lets the steam escape sideways and the lid stays flat. Brush all over with beaten egg and cut two small slits in the centre for steam.
7. Bake for 30–35 minutes until the pastry is puffed, deeply golden and shatteringly crisp, with the sauce bubbling lazily at the edges. If the top is browning faster than 25 minutes, drop the oven 10°C; you want bronze, not bitter.
8. Rest for 10 minutes so the filling settles and the sauce thickens to a proper spoonable consistency. Take the pie to the table whole, scatter the snipped chives over the lid, finish with cracked black pepper, and serve with buttery mash or steamed greens alongside.