Name: Leek and Mushroom Potato Pie (Puff Pastry)
Prep time: 30 min
Cook time: 30 min
Total time: 60 min
Ingredients: 1.1 pounds leeks (rinsed thoroughly, finely chopped); 1.1 pounds regular mushrooms (wiped, finely chopped); 0.32 ounces dried porcini mushrooms (plus 4-5 tablespoons of water for soaking); 1⅓ pounds potatoes (waxy (Yukon Gold, Charlotte), peeled, halved or cubed (peeled weight)); 4 tablespoons parsley (finely chopped); 3 tablespoons fromage blanc/fromage frais (or creme fraiche, sour cream); 2 tablespoons cornstarch/UK corn flour; ½ teaspoon onion granules; ⅓ cup+1tbsp water; 3-4 tablespoons olive oil; 1 sheet ready rolled puff pastry (375g/13.43oz); 1 small egg (lightly beaten); Fine sea salt and pepper to taste

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This leek and mushroom pie with potatoes is not only deliciously comforting and satisfying but also healthy. It’s full of flavour, brimming with vegetables, low in fat and comes with a light and crispy puff pastry topping.

Side view of leek and mushroom pie topped with golden brown pastry on white bowl with fork, plaid red-and-white cloth to the right, pie in dish and mushrooms in background.

This nourishing leek and mushroom pie is a fantastic one-pot dinner idea the whole family will love. It contains a handful of ingredients and is very simple to put together. You won’t need complicated spices, salt and pepper will suffice. Enjoy it as a vegetarian main dish or alongside chicken or turkey.

Leek and mushroom pie ingredients

Leeks

Leeks are quite sweet so pair really well with earthy mushrooms. Ensure you rinse your leeks well before slicing to remove any soil. Also, after you’ve chopped the dark green bits you can rinse them again in a strainer (optional). Drain thoroughly before putting in the pan.

Mushrooms

I used a fair amount of regular mushrooms as well as a bit of dried porcini mushrooms for extra richness and intensity of flavour. Porcini mushrooms can be expensive (unless you get them from a Polish delicatessen, which I recommend you do) but you’ll only need to use a few so this is still a pretty frugal recipe. Even a very small amount of porcini (I used 9 grams) will add loads of flavour to your pie.

I like to add a bit of porcini to most of my mushroom recipes, which include vegan cabbage rolls with mushrooms, creamy mushroom potato soup as well as chicken and mushroom casserole.

Potatoes

Use waxy potatoes which will hold their shape well in cooking, such as salad or baby potatoes. In the UK waxy potato varieties include Charlotte, Maris Peer and Jersey Royals. If you are in the US use Yukon Gold. You can cube the potatoes rather than just halve them as I have done. This is personal preference.

Puff Pastry

Remove the pastry from the fridge at least 30 minutes before making the recipe. If you are using frozen pastry defrost it in the fridge overnight.

Step-by-step recipe instructions

1.Boil the potatoes in salted water with a bay leaf until fully cooked but still firm. Drain well and place in the bottom of your pie dish. While the potatoes are boiling make the filling.

Peeled, halved potatoes in oval casserole dish.

2. Rinse the porcini mushrooms rubbing gently with your fingertips to remove any grit, then place in a small bowl and add a little water just to cover the porcini (about 4 tablespoons). Leave to soak while you prepare the other ingredients.

Dried porcini mushrooms in small white bowl with water.

3. In a frying pan heat up 2 tablespoons of oil and fry the leeks slowly over a low-medium heat for about 10 minutes until softened but not browned, stirring often. Season to taste and transfer into a bowl. Preheat the oven to 425 F/ 220 C/ gas mark 7 (fan 200 C/ gas mark 6).

Chopped leeks in large skillet with black spatula to the right.

4. In the same pan heat up 2 more tablespoons of oil and fry the mushrooms over a fairly high heat for about 6 minutes until they reduce in volume and release water. Chop up the porcini, add into the mixture (along with the water they soaked in) and stir in the parsley (if using).

Chopped mushrooms and parsley in large skillet.

5. Add the leeks, corn flour, onion granules and fromage frais. Stir and continue cooking until the mixture thickens. Add in the water, stir, season generously and remove from the heat.

Chopped leeks, mushrooms, yogurt and flour in large skillet with red spatula.

6. Pour the mixture over the potatoes.

Creamy mushroom and leek mixture in oval casserole dish.

7. Place your pastry sheet over the top and trim to fit your dish gently sealing along the edges and removing any air pockets. Make a little cut in the centre to allow excess steam to escape and brush the pastry with the egg wash.

8. Bake in the centre of the oven for 30 minutes or until golden brown. If the pastry starts to brown too much after 20 minutes cover it loosely with parchment paper or foil. Remove from the oven, rest for 5 minutes then serve.

Pie with golden brown pastry on top in oval dish.

Top tips for making mushroom and leek pie

Make ahead: You can boil the potatoes in advance and once cooled refrigerate until you are ready to make the recipe. Also once you’ve assembled the pie you can refrigerate it overnight and bake the following day (ensure the pie filling has had time to cool down before covering it with the pastry).
Substitutions: I used fresh parsley but you could swap that for a bit of thyme (1 tsp) or not use any herbs at all. I also used naturally low in fat fromage frais, but you can use crème fraiche instead if you prefer (though keep in mind it’s much more calorific).
Baking: If the pastry starts to brown too much after 20 minutes in the oven, cover it loosely with baking paper or foil.
Best served immediately while the pastry is hot and crispy.
Freeze it: Freeze the pie, uncooked, covered, for up to 3 months. Bake from frozen (do not freeze the pie if you’ve used previously frozen pastry to make it).

Another healthy vegetarian pie you might like is vegetarian sausage pie with mushrooms and sweet potato. Check out also this collection of over 12 healthy vegetarian pasta meals.

Mushroom and leek pie topped with golden brown pastry in white oval dish with spoon, mushrooms and pie in white dish in background.

Keep in touch!

If you make this healthy leek and mushroom pie with potatoes I'd love to know how it turned out for you. Let me know in the comments below, thanks!

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