Onion Tart with Lancashire Cheese - Perfect combinations

Slice of Onion Tart with Lancashire Cheese

I was saving this recipe for the the day I managed to plant this year's onion sets but, with the unrelenting cold we've been experiencing, I've decided this undeniably rich tart is exactly right for now.  I like to tell  myself a helping of watercress off-sets the richness!

Last year's store of onions have long gone and the onion sets I planted to overwinter are nowhere to be seen.  Some November-planted garlic clings on tenaciously but the leeks, which usually grow so well, are stunted.  A mixture of clay soil, copious rain and prolonged, numbing, cold has taken its toll.  My bio-dynamic planting calendar tells me it will be mid-April before I can start my Spring planting - assuming winter releases its icy grip.

Onion Tart with Lancashire Cheese

So, while I wait impatiently to get planting, I'm grateful to Simon Hopkinson for reminding me what a joyous combination cheese and onion make.  This recipe is adapted from his Onion Tart in Roast Chicken and Other Stories in which he mentions his mother's love of mixing a little Lancashire cheese into the filling. It's certainly a winning combination, though I prefer to scatter the Lancashire on the top just before baking.  A version of this tart is sometimes on the menu at 40 Maltby Street where an oat pastry is used.  Though more difficult to work with, it works as a great counter-balance to the richness of the filling.  Making this dish does leave you with a lot of egg whites, but that just gives you the excuse for a batch of meringues or macarons.

Onion Tart with Lancashire Cheese 
(Serves 4-6)

Shortcrust pastry:
100g (4oz) plain flour
50g (2oz) cold butter, diced
1 egg yolk
1 tablespoon cold water
Pinch of salt

Filling:
75g (3oz) butter
4 medium-large onions, thinly sliced
4 egg yolks
300ml (1/2 pint) double cream
Salt & pepper
75g (3oz) Lancashire cheese

Lightly butter a 20cm (8 inch), 3cm deep loose-bottomed tart tin and chill.  To make the pastry, sift flour, add salt and rub in the butter.  Add egg yolk and water and stir with a knife until the mixture comes together.  Use your hands to form it into a smooth ball, working the pastry as little as possible.  Wrap and chill for 30 minutes.

Melt the butter for the filling in a frying- or sauce-pan with a lid.  Add the onions and a little salt and pepper, stirring to coat the onions in the butter.  Cover with the lid and cook very gently, without browning, until the onions are soft (about 40 minutes).  The mixture will be very wet.  Remove the lid and cook down on a low heat for a further 15-20 minutes until the moisture has mostly disappeared.  Transfer to a bowl and leave to cool.

Pre-heat the oven to 200C (fan oven 180C).  Roll out the pastry as thinly as possible and line the prepared tart tin with it.  Prick the base of the pastry and chill for 15 minutes.  Line with greaseproof paper and fill with baking beans to bake blind in the oven for 10 minutes.  Remove the paper and beans and return the tart to the oven for a further 5 minutes or so to cook the base thoroughly.  Remove from the oven and turn down to 180C (fan oven 160C).  

Lightly beat the egg yolks with the cream.  Mix in the onions and season with salt and pepper.  Place the tart tin on a baking tray and pour the mixture into the tart case as high as you dare before crumbling the cheese on top.  Bake for around 35 minutes until the filling is set and lightly browned.

Peppery watercress goes very well with this tart.