For the pastry case:
300g plain flour
120g salted butter
1 small free-range egg
For the filling:
500g fresh asparagus, stalks trimmed
1 medium onion, finely diced
1 clove garlic, minced
50g salted butter
4 free-range eggs
4 free-range egg yolks
300ml double cream
Salt and pepper
A little chopped parsley (optional)
A flan tin, about 10” in diameter
A baking sheet to hold the tin
Baking beans & baking parchment.
Firstly, let’s make the pastry. In a food processor, whizz the butter and the flour together, then add the egg and process just until the mixture starts to come together. Tip onto a floured surface, and bring together into a ball. Wrap in clingfilm, and refrigerate for half an hour. Then, roll out the pastry and gently ease it into the flan tin, making sure it goes into the ‘corners’. Don’t take the edges off – we do this when the tart is cooked. Set the oven to Gas 5 / 190C / 375F. Cut a circle of baking parchment about three inches wider than the tart itself, and screw it up into a ball. Unfurl it carefully, and push into the pastry case gently. Screwing up the paper enables it to go into the corners of the tart perfectly. Fill the parchment with baking beans, and bake the tart for about 20 minutes, or until set in position, and then remove the parchment carefully. Bake the tart for a further 5 minutes to fully cook the base. Allow to cool while you prepare the filling. Reduce the temperature of the oven to Gas 3 / 160C / 325F.
Now to make the custard. Whisk the eggs together, and add the cream. Season a little, and add the parsley if you’re using it. Cut the asparagus into inch-long pieces. In a pan, gently sweat the onion and garlic in the butter. Cover and allow to simmer on a very gentle heat for at least 30 minutes. Cooking all the acid out of the onion makes for a smoother custard. Drain the onions, and spread around the base of the pastry case. Add the asparagus, and fill the case with the custard mix. I find it best to half-fill the tart before it goes into the oven, and finish it off as it sits on the shelf. That way it doesn’t end up all over the floor, and you get the custard all the way to the top. Bake the tart for 30-45 minutes, or until just wobbly and set. If the top starts to brown too much, cover it gently with a sheet. Allow to cool slightly, and then serve.
Next week, we’ll be going asparagus crazy again – I won’t apologise for exploiting this most fleeting of ingredients!