Onion and Gruyère Tart
This is my favourite savoury tart; a delicious mix of slowly caramelised onions and Gruyère cheese. It’s easy to make the Parmesan pastry with a food processor.
- 225g(8oz) plain ﬂour, plus extra for dusting
- 125g(8oz) butter, cubed
- 30g (1¼oz) Parmesan cheese
- 1 medium egg, beaten
- For the filling:
- a knob of butter
- 1tbsp olive oil
- 500g (1lb2oz) onions, thinly sliced
- 4 large eggs
- 300ml (10ﬂoz) double cream
- 150ml (5ﬂoz) milk
- 200g (7oz) Gruyère cheese, grated
- 30g (1¼oz) Parmesan cheese, grated
- salt and black pepper
1 Line a 24–25cm (9½–10in) deep round loose bottom tart tin.
2 To make the pastry, put the ﬂour, butter and Parmesan in a food processor. Whizz until it looks like breadcrumbs. Add the egg and 1 tablespoon of water and whizz until the mixture forms a ball. Roll out on a clean, lightly ﬂoured work surface and line the base and sides of the ﬂan tin with the pastry. Set aside to chill in the fridge for 30–35 minutes.
3 Preheat the oven to 220°C/425°F/Gas7. Prick the base of the ﬂan pastry and line with baking paper and then baking beans. Blind bake the pastry for 10 minutes. Remove the beans and bake for a further 8–10 minutes until lightly golden, then place the pastry case on a baking sheet.
4To make the ﬁlling, melt the butter and olive oil in a frying pan. Add the onions and fryover a medium– high heat for 5 minutes. Cover with a lid and gently simmer for 20 minutes until soft and golden brown. Spread onto the base of the tart.
5 Beat the eggs in a bowl. Add the cream and milk and season. Add the Gruyère,then pour into the case.Sprinkle with the Parmesan.
6 Reduce the oven to 180°C/350°F/Gas4. Bake for about 30–35 minutes until lightly golden on top and set in the middle.