Pie is universally loved, and my leek & mushroom pie is a comforting, plant-based take that’s hearty enough to satisfy meat-eaters too. With sweet leeks, meaty mushrooms and protein-rich lentils in a silky white sauce with a hint of mustard, finished with creamy mashed potato, this recipe is a delicious slice of comfort food.
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WHY SHOULD I COOK IT?
This leek & mushroom pie is perfect whether you’re fully vegan or simply embracing meat-free days. The combination of sweet leeks, hearty mushrooms and tender lentils in a creamy, mustard-kissed white sauce, topped with smooth mashed potato, creates a satisfying, comforting dish without relying on pastry.
WHAT’S THE OCCASION?
Ideal for a cosy dinner by the fire, a special Sunday lunch or a make-ahead weeknight meal.
HOW LONG WILL IT TAKE ME?
Expect just over an hour from start to finish: roughly 35 minutes of hands-on prep and 25–30 minutes in the oven. You can assemble the pie ahead of time, refrigerate it covered, and bake when you’re ready.
IS IT DIFFICULT?
Not at all. The recipe is straightforward with simple chopping and basic cooking techniques. The white sauce is made foolproof by whisking a flour-milk paste before simmering. Difficulty: 6/10.
WHY IS IT HEALTHY?
This pie is nourishing as well as comforting. Mushrooms provide vitamin D and selenium, leeks add fibre, and lentils bring plant-based protein. Using mashed potatoes instead of pastry keeps it lighter without sacrificing flavour.
WHAT EQUIPMENT DO I NEED?
You’ll need a knife and chopping board, two saucepans (one with a lid), a measuring jug and whisk, tongs, a potato masher and a medium pie dish.
TIPS FOR THE BEST LEEK & MUSHROOM PIE EVER
- No lumps, please! Use floury potatoes such as King Edward or Maris Piper. After boiling, drain and return to the pan to dry briefly over very low heat. Mash with a hand whisk, masher or ricer, then beat in a splash of plant milk and plenty of seasoning until completely smooth and creamy.
- Whisk, whisk, whisk. To ensure a silky white sauce, make a paste by whisking the flour with a little milk first, then slowly add the remaining milk while whisking. Whisk constantly while the sauce simmers so it thickens evenly without lumps.
- Want extra crispy bits? For crisp, bubbling edges, finish the pie under the grill for a few minutes after baking until golden and bubbly around the sides.
If you make this leek & mushroom pie I’d love to see your photos — tag me on Instagram or leave a comment below. Keep smiling! G x
LEEK & MUSHROOM PIE
Sweet leeks, meaty mushrooms and tender lentils all united in a velvety white sauce with a touch of mustardy heat and finished with creamy mashed potato. It’s nourishing plant-based comfort food at its finest! Vegan & GF.
Main Course
British
Ingredients
-
750
g
potatoes -
375
ml
plant-based milk
(I use oat milk) -
2
tsp
wholegrain mustard -
2
tbsp
extra virgin olive oil -
3
leeks
sliced -
500
g
mushrooms
quartered -
3
cloves
garlic
minced -
2
tsp
herbs de Provence -
1
400g can
green lentils
drained & rinsed -
25
g
gluten-free flour -
25
g
olive oil -
2
tbsp
nutritional yeast
(optional) -
15
g (1/2 bunch)
fresh parsley - Sea salt & freshly ground black pepper
Instructions
-
Preheat oven to 180°c fan / 200°c / 390°f.
-
Peel and cube the potatoes. Bring a large pan of salted water to the boil and add the potato chunks. Cook for 15 minutes or until very tender. Drain in a colander, return to the pan and dry over a very low heat for 2 minutes. Add a dash of plant-based milk, 1 tsp wholegrain mustard and plenty of salt and pepper. Mash until smooth.
-
Heat a large lidded saucepan over medium heat and add 2 tbsp extra virgin olive oil. Add the leeks and cook, uncovered, for 5 minutes until slightly softened. Add the mushrooms and garlic and cook for a further 5 minutes. Stir in the lentils and herbs, reduce the heat, cover and sweat for 10 minutes until the mixture has softened and reduced.
-
Meanwhile make the white sauce. In a jug, whisk the gluten-free flour with a small amount of the plant milk to form a paste. Gradually whisk in the remaining milk, then stir in 25g olive oil. Transfer to a saucepan and simmer gently over medium heat, whisking constantly for 5–8 minutes until the sauce coats the back of a spoon. Stir in the remaining mustard and nutritional yeast if using, then season with salt and pepper. Remove from the heat.
-
Pour the white sauce into the leek and mushroom mixture and combine. Transfer the filling to a medium pie dish, spoon the mashed potato on top and smooth. Bake for 25–30 minutes until the top is golden and edges are bubbling and crisp. Scatter with chopped parsley and serve.
Recipe Notes
You can assemble this pie up to 3 days ahead: cover and refrigerate, then bake from chilled following the recipe times.
Nutritional yeast is a common vegan ingredient that adds a cheesy flavour. If you prefer, substitute equal quantities of parmesan or a dairy-free equivalent, or omit it entirely.