Quick Recipe Version (TL;DR)
Quick Ingredients
- 700 g boneless, skinless chicken thighs, cut into 2 cm chunks
- 3 large leeks (white and light green parts), cleaned and sliced
- 3 tbsp unsalted butter, divided
- 1 tbsp olive oil
- 2 garlic cloves, minced
- 1 tsp fresh thyme leaves (or 1/2 tsp dried)
- 3 tbsp all-purpose flour
- 1/2 cup dry white wine (125 ml), optional
- 2 cups low-sodium chicken stock (500 ml)
- 1/2 cup heavy/double cream (120 ml)
- 1 1/2 tbsp Dijon mustard
- 2 tbsp finely chopped fresh parsley, plus extra to garnish
- 1 tsp lemon juice, optional
- 1 sheet all-butter puff pastry (375 g), chilled
- 1 large egg beaten with 1 tbsp milk (egg wash)
- Salt and freshly ground black pepper
- Buttered greens: 250 g fine green beans, 150 g peas, 1 tbsp butter, lemon zest
Do This
- 1. Heat oven to 400°F/200°C (fan 180°C). Keep pastry cold. Butter a 2-liter baking dish.
- 2. Brown chicken in 1 tbsp butter + 1 tbsp oil, 4–5 minutes; season and set aside.
- 3. Soften leeks with remaining 2 tbsp butter, garlic, and thyme, 7–8 minutes. Stir in flour; cook 1 minute.
- 4. Deglaze with wine (optional). Gradually whisk in stock; simmer 3–4 minutes until thickened. Stir in cream, Dijon, parsley, and lemon; season.
- 5. Return chicken to sauce; simmer 2 minutes. Spoon into baking dish. Cool 5 minutes.
- 6. Top with pastry, crimp, vent, brush with egg wash. Bake 25–30 minutes until puffed and deeply golden.
- 7. Boil beans 3–4 minutes; add peas for 1 minute. Drain; toss with 1 tbsp butter, lemon zest, salt, pepper. Rest pie 10 minutes; serve.
Why You’ll Love This Recipe
- Comforting and elegant: creamy mustard-parsley sauce under a bronzed, flaky puff-pastry lid.
- Balanced flavor: sweet leeks, juicy chicken thighs, tangy Dijon, and fresh herbs.
- Weeknight-friendly with store-bought puff pastry and simple techniques.
- Make-ahead friendly; freezes well for future cozy dinners.
Grocery List
- Produce: Leeks, garlic, fresh thyme, fresh parsley, lemon, green beans, peas
- Dairy: Unsalted butter, heavy/double cream, 1 large egg, milk (for egg wash)
- Pantry: Olive oil, all-purpose flour, Dijon mustard, chicken stock, dry white wine (optional), puff pastry, salt, black pepper
Full Ingredients
Chicken & Leek Filling
- 700 g boneless, skinless chicken thighs, cut into 2 cm chunks
- Salt and freshly ground black pepper
- 1 tbsp olive oil
- 3 tbsp unsalted butter, divided
- 3 large leeks (white and light green parts), cleaned well and sliced 1 cm thick
- 2 garlic cloves, minced
- 1 tsp fresh thyme leaves (or 1/2 tsp dried)
- 3 tbsp all-purpose flour
- 1/2 cup dry white wine (125 ml), optional
- 2 cups low-sodium chicken stock (500 ml), warm
- 1/2 cup heavy/double cream (120 ml)
- 1 1/2 tbsp Dijon mustard
- 2 tbsp finely chopped fresh parsley, plus extra to finish
- 1 tsp lemon juice (optional, to brighten)
To Assemble & Bake
- 1 sheet all-butter puff pastry (375 g), kept chilled
- 1 large egg beaten with 1 tbsp milk (egg wash)
- Flaky sea salt, for sprinkling
Buttered Greens (Side)
- 250 g fine green beans, trimmed
- 150 g peas (fresh or frozen)
- 1 tbsp unsalted butter
- 1/2 tsp finely grated lemon zest
- Salt and freshly ground black pepper
Step-by-Step Instructions
Step 1: Preheat and prep your dish
Heat the oven to 400°F/200°C (fan 180°C). Lightly butter a 2-liter baking dish (about 9-inch square or similar). Keep the puff pastry in the fridge so it stays cold and puffs beautifully later.
Step 2: Brown the chicken
Pat the chicken dry with paper towels and season with 1/2 tsp salt and 1/4 tsp pepper. Heat 1 tbsp olive oil and 1 tbsp butter in a large, deep skillet over medium-high heat. Add the chicken in a single layer and brown for 4–5 minutes, stirring once or twice, until lightly golden (it does not need to be fully cooked). Transfer to a plate, leaving the tasty browned bits in the pan.
Step 3: Soften the leeks and aromatics
Reduce heat to medium. Add the remaining 2 tbsp butter. Stir in the leeks, a pinch of salt, garlic, and thyme. Cook for 7–8 minutes, stirring often, until the leeks are silky and sweet but not browned. Sprinkle over the flour and cook for 1 minute, stirring, to remove the raw taste.
Step 4: Build the creamy mustard sauce
Deglaze the pan with the white wine (if using), scraping up any browned bits; simmer 1 minute. Gradually whisk in the warm chicken stock, then simmer 3–4 minutes until the sauce thickens and turns glossy. Stir in the cream, Dijon mustard, parsley, and lemon juice (if using). Taste and season with salt and pepper. The sauce should coat the back of a spoon; if too thick, loosen with a splash more stock; if too thin, simmer another minute.
Step 5: Bring the filling together
Return the browned chicken and any juices to the pan. Simmer gently for 2 minutes to heat through. Take off the heat and let the filling stand for 5 minutes; this brief cool-down helps keep the pastry from melting when placed on top.
Step 6: Assemble and bake
Spoon the filling into the prepared baking dish. Roll the pastry slightly, if needed, to fit the dish with a small overhang. Drape over the filling, trim excess, and crimp the edges with a fork. Cut 3 small slits in the center to vent steam. Brush with egg wash and sprinkle a pinch of flaky sea salt. Bake for 25–30 minutes, until the pastry is dramatically puffed and deep golden and the filling is bubbling at the edges. Rest the pie for 10 minutes before serving so the sauce settles.
Step 7: Make the buttered greens
While the pie bakes, bring a pot of salted water to a boil. Cook green beans for 3–4 minutes, then add peas for 1 minute more. Drain well and toss with 1 tbsp butter, lemon zest, salt, and pepper. Serve alongside generous scoops of the pie, garnished with extra parsley.
Pro Tips
- Keep pastry cold: a chilled sheet puffs higher. If your kitchen is warm, pop the assembled pie in the fridge for 10 minutes before baking.
- Clean leeks thoroughly: slice, then swish in a bowl of cold water to remove hidden grit; drain well.
- Thicken to the right stage: the sauce should coat a spoon; too thin yields a watery pie, too thick feels heavy.
- Let it rest: 10 minutes after baking prevents a runny slice and keeps the pastry crisp.
- No wine on hand: skip it and add an extra 2 tbsp stock plus a tiny splash of vinegar or lemon for brightness.
Variations
- Bacon and mushroom: sauté 100 g diced bacon and 200 g sliced mushrooms after browning the chicken; proceed as directed.
- Tarragon twist: swap parsley for 1–2 tbsp chopped fresh tarragon and add 1 tsp wholegrain mustard alongside the Dijon.
- Leftover roast chicken: use 700 g cooked chicken, skip the browning step, and warm gently in the sauce in Step 5.
Storage & Make-Ahead
Cool leftovers quickly, cover, and refrigerate for up to 3 days. Reheat at 350°F/175°C for 20–25 minutes (cover pastry loosely with foil if it browns too fast) until piping hot in the center. Freeze the cooled filling for up to 3 months, or assemble the pie unbaked and freeze, well-wrapped. Bake from frozen at 400°F/200°C for 45–55 minutes, covering with foil for the first 25 minutes; ensure the center is bubbling and the internal temperature of the filling reaches 165°F/74°C. The buttered greens are best made fresh.
Nutrition (per serving)
Approximate values: 670 kcal; 42 g fat; 46 g carbohydrates; 27 g protein; 2.2 g sodium; 4 g fiber. Values will vary based on brands and portion sizes.
