This vegetarian pie serves six and is great to serve when you have guests round for lunch. Celeriac, potatoes, chestnuts and wild mushrooms combine in a creamy filling.
Prep time: 20 minutes | Cooking time: 55 minutes
- 500g potatoes (I like Maris Piper)
- 500g celeriac
- 425ml double cream
- 140ml sour cream
- 85ml whole milk
- 2 garlic cloves, very finely sliced
- 2 sprigs thyme, leaves only
- 200g fresh wild mushrooms or chestnut or oyster mushrooms, or a mixture
- 15g unsalted butter
- 100g cooked chestnuts, vacuum-packed or frozen
- 300g puff pastry
- 2 egg yolks, beaten with 3 tsp milk
- Peel the potatoes and celeriac and slice very finely (almost wafer-thin); a mandolin does the best job but you can also use a very sharp knife.
- In a large saucepan, mix together the creams and milk and bring to just under the boil. Add the sliced potatoes and celeriac, garlic and thyme and cook gently for five to seven minutes. The vegetables should be starting to soften.
- Chop the mushrooms. Melt the butter in a frying pan, add the mushrooms and sauté briskly over a medium-high heat, seasoning them as they cook. You want to get a good colour and also cook off the moisture, otherwise they will make your pie watery.
- Slice the chestnuts. Season the potatoes and celeriac well and spoon half into a buttered pie dish (you will need one with a lip, so it’s easier to attach the pastry). Lay the chestnuts and mushrooms on top, then spoon on the rest of the vegetables. Leave to cool. Preheat the oven to 200C/gas mark 6 and put a baking sheet into it.
- Roll the pastry out on a lightly floured surface to the thickness of a one pound coin. Cut strips of pastry the same width as the lip of the pie dish, enough to cover all the way round.
- Brush the egg yolk mixture over the lip and press the pastry strips on to it. Cut out a lid, a little larger than your dish. Brush the pastry on the lip with egg wash and put the lid on top, pressing it down to seal.
- Use leftover pastry to decorate the top and make three tiny slits near the centre. Brush with the egg wash.
- Bake in the oven for 40 minutes, putting the dish on top of the baking sheet, until the pie is golden and the vegetables are tender.