Recipe: Puff Pastry Tart with Celeriac, Butternut Squash & Walnut Pesto

Puff pastry tarts are so versatile and look lovely but are really easy to make. The combination of earthy celeriac and walnuts with sweet squash and tangy cheese comes together beautifully to make a simple dinner that reheats well in the oven for lunch the next day.

You can make this with any pesto, but the below walnut one is really quick to make in a food processor. This will make about twice as much as you need, use the rest as you would any pesto.

If you’re not sure where to start with a celeriac, check out the tips beneath the method for how to prep it up.

Serves 4

Ingredients

Tart
500g puff pastry
300g butternut squash, peeled (about half a medium squash)
½ a celeriac, peeled
1 egg, beaten
2 tablespoons pesto
40g tangy cheese: e.g. Manchego, mature cheddar, feta 

Walnut pesto
30g fresh basil
Juice ½ lemon
½ clove garlic, crushed
30g Parmesan or vegetarian alternative
100g walnuts
About 150ml good quality olive oil 

Method

1.      Pre-heat the oven to 180C / gas mark 4.

2.      Finely slice the squash and celeriac, about the thickness of a pound coin. Lay them in a single layer on a couple of baking trays, coat with oil and roast for approximately 15 minutes until just soft (the celeriac might need a bit longer than the squash). Transfer all the veg onto one tray, leaving the second tray oily – keep the oven on.

3.      While the veg is roasting, whizz the pesto ingredients in a food processor. Don’t add all the olive oil at once - pour it in gradually, stopping to scrape the sides of the food processor down as you go until you reach the right consistency. You might not need it all. Check the flavours and adjust to your taste – more lemon, more garlic, more pepper etc.

4.      Roll out the puff pastry to the size of your now-vacant baking tray, again to about the thickness of a pound coin. Transfer the puff pastry to the oiled tray (the easiest way to do this is to roll it over the rolling pin then back out into the tray), and then use a fork to gently prick all over the sheet, leaving a 1 inch border like a frame. This stops the middle of the tart puffing up when you bake it.

5.      Spread two generous tablespoons of the pesto over the middle of the pastry, again leaving a clear border around the edges. Lay over the roasted veg, overlapping them as you go.

6.      Brush the pastry border lightly with beaten egg.

7.      Sprinkle grated cheese over the veg – using a peeler works well for hard cheese.

8.      Bake for 20 minutes until the tart is golden brown and the border puffs up. You might want to turn the tart 180 degrees half-way through baking so it browns evenly.

Prepping Celeriac
At first sight the celeriac can look an intimidating vegetable, all gnarled and fibrous, but it’s really a simple matter of getting rid of that tough exterior to use the firm, snowy root inside.

Give it a good scrub, then I like to have at it with a potato peeler, getting rid of the outer layer of skin until you have an almost smooth white surface. There will probably be some tangles left at the root end, so just cut those off with a kitchen knife and you’re good to go: cut into chunks to boil for mash or soup; into matchsticks or grated for a creamy remoulade; into slices for a tart or dauphinoise or fingers to roast.