Jean's Summer Onion Tart

|This is a great dish to share with friends bring to a summer picnic or share with family at home.||900g onions5g butter1 tablespoon olive oil250g plain flour125g butter2 eggs125g milk or cream75g grated gruyere cheesesalt and pepperpinch of nutmeg|Cover onion and cook on a low heat for an hour till really soft a sweet. Stir in 1 tbs flour and cook for a further 3 mins and leave to cool.Mix salt into flour rub in butter add enough cold water to bind. Chill for 30 mins.Line a shallow 25cm or deep 22cm pie dish with the pastry and bake blind at 200c till just coloured.Beat egg cream and seasoning together mix in onion and half of the cheesePour into pastry case and sprinkle remaining cheese on topBake for 25 to 30 mins at 180c till firm and golden|60.00 minutes|10|https://www.localgreens.org.uk/recipes/jeans-summer-onion-tart