Stilton, Potato & Caramelised Onion Tart

Whenever we go into a cheese shop the first thing my 2 year old son will do is ask for stilton.  Usually at the top of his voice, much to the amusement of anyone in earshot.  He's well known at both of our local cheese haunts - The Cheese Block and Mootown (whose Bermondsey Spa he is also quite partial too, especially when eaten straight off the knife) - for his adventures in strong, mature and stinky cheese.

It's hardly surprising though given the quantities of blue cheese I used to demolish as my parents pushed me around the market on a Saturday morning in my pushchair whilst they did their weekly shop.  My personal favourite was Danish Blue at that time, or so my Dad tells me.

Back in February we spent a week holed up in a converted barn in the foothills of the Black Mountains.  It was the sort of holiday where we sheltered from the freezing temperatures outside, ate copious amounts of cheese and pottered around the kitchen baking focaccia, coconut breakfast cake, cinnamon buns and savoury tarts. 

This tart, packed with new potatoes, caramelised onions and stilton, is what I'd refer to as a substantial tart.  The sort you only need a simple salad with in summer.  I'd had the idea for it in mind for quite a while, so baked it for the first time that week in Wales and more recently for my Tea Room at the Sunday Art Salon in Brockley.

I like it best when it's served cold for lunch or a picnic the next day.

Ingredients

For the pastry:

225g plain flour
110g unsalted butter
pinch salt
125ml cold water

For the filling:

5 medium onions
1 tbsp rapeseed oil
1 tsp soft brown sugar
1 tsp sherry vinegar
100g-150g good stilton, broken into pieces
6 medium new potatoes, cooked and sliced
300ml double cream
2 medium eggs
salt & black pepper

Method

Start by making the pastry.  Put the flour, salt and butter in a mixing bowl and rub together with your finger tips until they resemble breadcrumbs.  Add the cold water, a little at a time, and bring together to form a ball (you may not need it all), handling the pastry lightly and as little as possible.  Flatten into a patty, wrap in cling film and chill in the fridge for at least 30 minutes.

Preheat the oven to 200C.

Peel and halve the onions, then slice into 'half rings' about 5mm thick.  Heat a heavy based frying pan over a low heat, add the rapeseed oil and fry the onions for 15 to 20 minutes, stirring often, until they are golden brown.  Don't try to rush this, they need to cook slowly to develop the flavour.  Add the sugar and season with salt and pepper.  Cook for a couple of minutes and then add the sherry vinegar and cook for another minute.

Roll the pastry out to about 3mm thick and line a greased 23cm fluted, loose based tart tin.  Prick the surface of the pastry on the base of the tin gently all over with a fork, taking care not to push through to the tin.  Chill again for 10 minutes.  Line with foil or baking parchment and fill with baking beans.  Bake blind for 15 minutes, then remove the beans and foil / parchment and bake for another 5 minutes until the pastry has dried out and the base is cooked.

Reduce the temperature of the oven to 180C.

Spread the caramelised onions over the base of the cooked pastry case.  Top with the cooked potato slices and then the stilton.  Whisk the eggs and cream together and season with a little salt and plenty black pepper.  Pour over the onions, potatoes and stilton until it nearly reaches the top of the pastry.

Cook the tart in the middle of the oven for 15-20 minutes until set and the pastry cooked through.  If the pastry around the edge is cooking too quickly you can cover it with foil.  

Leave to cool in the tin before removing to serve.