A pissaladière that you would find in the south of France usually has a very thin dough as its base-a sort of onion pizza which is in keeping with its Mediterranean roots. But this version made with puff pastry reminds me of the absolutely delicious squares we used to buy when students in Paris. Try and find the all-butter puff pastry –it is far superior in flavour to the ordinary variety. I heap on the anchovies (which I will gladly eat straight from the tin) but you can use half the amount if you are not such a fan of the salty little fillets.
- 3 tablespoons extra-virgin olive oil
- 875g onions, peeled and very finely sliced
- 2 garlic cloves, peeled and finely chopped
- 5 sprigs fresh thyme
- 2 teaspoons balsamic vinegar
- 375g ready-rolled puff pastry sheet
- 100g jar anchovies in oil, drained
- 12-16 black olives
- Heat the oil in a large, preferably lidded, frying pan or cast iron sauté pan. Add the onions, garlic, thyme and season with salt and some ground black pepper. Cover with a lid and leave to cook over a very low heat for about 35-40 minutes, stirring regularly to stop the onions from catching on the bottom of the pan. The onions should be really soft but not coloured.
- Remove the lid and turn the heat up slightly. Pour in the balsamic vinegar and cook for a further 15-20 minutes, stirring regularly. The onions should have turned a light golden colour and be almost mushy. Take off the heat and remove the thyme sprigs.
- Heat the oven to 200˚c, fan oven 180˚c, mark 6. Unroll the pastry and lay it on a large baking sheet- I keep it on the paper to stop it sticking. Spread the onions evenly over the pastry, leaving a margin of about 2cm around the edges. Halve the anchovies lengthways and arrange in a criss-cross fashion over the onions. Scatter over the olives. Bake in the oven for about 25 minutes until golden.