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Caramelized Onion and Cheese Tart

Introduction & method

This tasty tart is brilliant on a warm summer's day with a nice fresh salad. And it's vegetarian too.

Caramelized Onion and Cheese Tart Recipe

Caramelise the onions

Top and tail and peel the onions. Cut them in half, then thinly slice them - about 5mm, quarter of an inch. In a large frying pan on medium heat, melt the butter and heat up the oil. Add the onions and stir frequently. You want them to soften but not necessarily brown at this stage. Caramelization will take 45 to 60 minutes and it's a different process from burning the onions! After the initial softening, turn the heat right down and stir the onions every few minutes. Eventually they will turn golden brown and give up some of their sugars - they'll be sitting in what looks like jam. Take them off the heat and set aside.

Make the pastry

Cut the butter into small cubes. Place the flour in a large mixing bowl and stir in the salt. Rub the butter into the flour with your fingertips. When it's all rubbed in, it should look like coarse breadcrumbs. Now mix in the water. You can start with 4 tablespoons and mix those in. Then add 2 more and mix those in. It's possible that will be enough - if the dough is moist enough to hold together as a ball. If it doesn't, add a bit more water. Cover the dough and leave it in the fridge to rest for 15 minutes.

Make the pastry shell and blind-bake it

Preheat your oven to 160°C (320°F) for a fan/convection oven, 180°C (356°F) conventional, gas 4. You'll need a flan tin, 23cm (9 inches) diameter, preferably with a removable bottom. Grease the inside with butter if you don't trust the non-stick coating. Sprinkle some flour on your worktop and rolling pin, and roll the pastry out to a thin disc somewhat larger than you flan tin. Roll the pastry over your rolling pin, then unroll it over the tin. Use a spare bit of dough to press the dough right down to the bottom. Roughly trim the excess pastry around the edge. You'll probably have enough pastry left over to make a couple of small flans. Pierce the bottom of the pastry shell with a fork. Line the shell with scrunched-up greaseproof paper then pour dried beans, baking beans or rice in. Pop the shell in the oven for 10 minutes. Remove it from the oven and carefully lift out the greaseproof paper and beans/rice. Paint the inside of the shell with beaten egg and put it back in the oven for 10 more minutes.

Make the filling, bake the tart

Carefully trim the edge of the tart case so it's level with the top of the flan tin. Grate the cheese - you can use any cheese or combination of 2 or 3 cheeses. Mix it together with the soft cheese, eggs, oregano and caramelised onions. Stir in a bit of double cream or milk to loosen the mixture slightly - it shouldn't be too runny, but neither should it be too stiff. I know, useless description! Spoon the mixture into the pastry case and level off the top a little below the rim of the tin. Sprinkle the top with a little oregano. In my video of this, I topped the filling with some discs of mozzarella - I don't recommend this, it didn't look good! Bake the tart for about 30 minutes - it should be golden on top and the filling should feel set if you poke it with a finger. You can eat this tart hot or cold.

The video above is from the Keef Cooks YouTube channel. Click here to see the video recipe of Caramelized Onion and Cheese Tart on YouTube.


Ingredients & Info

 250 grams plain (AP) white flour
 125 grams cold butter
 1 tsp salt
 7 tbsp water
 250 grams cheese (cheddar/grana padano)
 100 grams soft cheese
 2 large onions
 1 tsp oregano
 2 tbsp butter
 2 tbsp sunflower oil
 4 eggs
 4 tbsp double cream

US Customary/Imperial

Serves 4 -6
Prep time: 15 minutes.
Resting time: 30 minutes.
Cooking time: 1 hour 40 minutes.
Total time: 2 hours 25 minutes.