Onion, thyme & Caerphilly tart with thyme pastry

This is based on Simon Hopkinson’s* luscious onion tart recipe: it makes full use of the way the plainest of onions turn sweet, soft and complex when given plenty of cooking time. Serves 4 100g plain flour 65g cold butter, cubed A pinch of salt A few stems of fresh thyme, leaves picked 2 tbsp iced water 1 egg, lightly beaten for the filling 50g butter 500g onions, very thinly sliced A few stems of fresh thyme, leaves picked 1 egg and 2 egg yolks 125g whipping cream 75ml soured cream 150g Caerphilly cheese, crumbled into chunks

1 Make the pastry: in a bowl or food processor, rub or blitz together the butter, flour and salt until they resemble breadcrumbs. If using a food processor, transfer to a bowl and add the thyme and water, then bring the mixture together with your hands, kneading briefly. Wrap in cling film and chill in the fridge for half an hour.

2 Preheat oven to 180C/Fan 160C/ Gas 4 and place a flat baking sheet on the middle shelf. Melt the butter in a wide-based pan and add the onions and thyme. Cook on a low heat for about 30 mins, stirring occasionally, until the onions have collapsed completely. Remove from the heat.

3 Roll out the pastry and line a 20cm tart tin, leaving the excess draped over the sides. Prick the base all over with a fork, and then blind bake for 15 mins: scrunch up and flatten out a large piece of baking parchment (scrunching softens it), then place it over the pastry and cover the base with dried beans or rice.

4 Once blind baked, remove the beans and paper and use a serrated knife held horizontally to saw off the excess pastry. Paint the case all over with beaten egg; bake for a further 15 mins.

5 To make the filling, beat the egg, egg yolks, whipping cream, soured cream and thyme together, season with salt and pepper, then mix this into the onions. Pour everything into the tart case and top with the pieces of Caerphilly. Bake for about 40 mins until golden and fairly firm to touch. Remove from the oven and leave to cool. Best eaten at room temperature.

Cheese and onion, but not as you know it – the onions, slowcooked, and paired with creamy Caerphilly