Celeriac, Leek and Mushroom Pie Recipe

Ash Tyrrell

Celeriac, Leek and Mushroom Pie Recipe

I still remember the first time I pulled this pie out of the oven and watched the pastry puff up into golden, flaky layers. The smell of tarragon and melted cheddar filled my kitchen, and I knew this one was a keeper. It's the kind of dish I make when I want something warm, hearty, and a little bit fancy without much fuss.

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Prep Time 20

Cook Time 1

Servings: 6

Ingredients Method Notes

Ingredients

10 g dried porcini mushrooms – these bring a deep savory richness, so don't skip them
3 leeks rinsed and thinly sliced – forms the sweet, mellow base of the filling
1 large celeriac about 750g, peeled and cubed – the earthy, hearty star of the pie
6 tablespoons extra virgin olive oil – for softening the vegetables until tender
1 teaspoon fine sea salt – helps draw out moisture as the vegetables cook
4 garlic cloves crushed – adds that essential savory backbone
250 g chestnut mushrooms sliced – use fresh mushrooms, never canned, for the best bite
1 teaspoon ground black pepper – adds a gentle warmth to the whole filling
3 tablespoons Dijon mustard – brings a tangy sharpness that balances the cream
100 g extra mature cheddar grated – grate it fresh for the smoothest, creamiest melt
100 ml double cream – makes the filling silky and rich
½ x 20g pack tarragon leaves picked – its subtle aniseed note is what makes this pie special
1 medium egg beaten – for brushing the pastry to a shiny, golden finish
320 g ready-rolled puff pastry – the flaky golden lid that pulls it all together

Method

Start by placing the dried porcini in a bowl and covering them with 250ml of just-boiled water. Let them soak for about 30 minutes while you slice the leeks and peel and cube the celeriac. This soaking step is what gives the filling its deep, savory flavor later on.
Heat the olive oil in a large saucepan and add the leeks, celeriac and salt. Cook for about 10 minutes until the leeks soften, then stir in the garlic, chestnut mushrooms and chopped porcini. Pour in the reserved porcini broth, cover, and simmer until the celeriac turns soft.
Stir the pepper, mustard and cheddar into the filling until melted, then fold in the cream and tarragon. Tip everything into your pie dish, top with the puff pastry, brush with egg, and cut a few slits for steam. Bake until the pastry turns golden and puffed.

Notes

I always grate my own cheddar instead of buying pre-shredded, since it melts so much smoother into the sauce.
I let the filling cool slightly before adding the pastry, otherwise the base can go soggy.
I use fresh tarragon whenever I can find it, because the flavor is so much brighter than dried.
I crimp the pastry edges firmly with my fingers so the filling doesn't leak out while baking.