Onion Tart Recipe

Onion tart

  • serves 4
  • Easy

Onion tarte tatin is hugely fashionable, but this tart is more old-school – almost a quiche, with long strands of just-caramelised onion in an unctuous savoury custard. We love it. It matches really well with an off-dry pinot gris from Alsace or nebbiolo, the barolo grape from northern Italy.



  • butter 100g, cold
  • plain flour 175g
  • gruyère cheese 50g, finely grated
  • egg yolk 1, beaten with 2 tbsp ice-cold water


  • butter 50g
  • olive oil
  • onions 800g, peeled and finely sliced
  • thyme 2 sprigs
  • eggs 2, plus 1 yolk
  • single cream 150ml
  • bitter leaf salad to serve


  • Step 1

    First make the pastry. Cut the butter into cubes and rub into the flour with your fingertips (or pulse in a food processor) until the mixture resembles fine breadcrumbs. Stir in a pinch of salt and the cheese.Add the egg yolk and water and mix with a knife or blend until bound. Wrap in clingfilm and rest in the fridge.

  • Step 2

    To make the filling, melt the butter with 2 tbsp olive oil in a large, heavy pan.Add the onions and fry gently until they are soft and beginning to colour. This will take about half an hour then leave to cool. Heat the oven to 200C/fan 180C/gas 6, roll out the pastry and use it to line a buttered deep sided 20cm or a shallow 23cm tart tin. Cover the base with greaseproof paper, fill with baking beans and bake for 15 minutes. Remove the paper and beans and cook for 5 minutes more.

  • Step 3

    Strip the thyme leaves from their stems and add to the onions. Mix the eggs, egg yolk and cream and season. Pour into the pastry case and cook for 15-20 minutes, or until the the tart is wobbly but just cooked. Serve with a bitter leaf salad.

Nutritional Information

  • Kcals 758
  • Fat 54.2g
  • Saturates 29.1g
  • Carbs 48.4g
  • Fibre 5.6g
  • Protein 16.4g
  • Salt 1.1g