Put the oil and butter into a frying pan, add the onions, cover and cook over a medium high heat, stirring occasionally, for 25–35 minutes. The onions will collapse and become brown.
Remove the lid, stir in the sugar and cook for a further 2 minutes then remove from the heat, cover and set aside.
Pre-heat the oven.
Put the flour and butter into a large bowl.
Using a pastry blender or fork, mash the butter into the flour until it resembles breadcrumbs.
Stir in enough the water to bring together a soft ball of dough.
Cover the dough and leave it to stand for 15 minutes.
Rub a little oil around the inside of a 23cm/9” quiche or tart dish.
Dust the work surface with flour, put the dough in the middle and sprinkle it with more flour.
Roll out the pastry into a circle 5cm/2” larger than your tin and lift it into the dish, OR simply press it into the baking dish using your fingers.
Cut away any pastry hanging over the edge of your dish.
Caramelized Onion Tart
Break the eggs into a mixing bowl, add the cream, salt and pepper and beat together well.
Add the caramelized onions to the bowl, stir to combine then tip the mixture into the prepared pastry base.
Bake for 45-50 minutes.
23cm/9” spring-form cake tin or quiche dish, pastry blender, mixing bowl and frying pan
180°C, Fan 160°C, 350°F, Gas 4
Overall a good recipe, but I felt it needed a few tweaks. I used 15 minutes of the cooking time to bake the pastry case ‘blind’ before adding the filling, which worked well (who wants soggy bottoms?). I also used 50% lard and 50% butter on my pastry, as I find all butter pastry too rich. A change I would make in future is not to add the tablespoon of brown sugar. It made the tart too sweet and if you have caramelised the onion properly then it will be sweet enough.