Buttery, flaky pastry, sweet onions and juicy tomatoes make this a proper summer tart. I add a layer of breadcrumbs to soak up some of the liquid from the tomatoes, and I salt them for a little while first and pat them dry all in an effort to intensify the flavour and stop the pastry going soggy – it’s an extra step but worth the effort.
Serves 4-6
4-5 large tomatoes (or whatever you have to hand from your garden)
1 large onion, finely sliced
1 clove of garlic, crushed
1 knob of butter
A good sprig of fresh thyme
1 package ready-rolled puff pastry
1 tbsp Dijon mustard
100g breadcrumbs
1 egg, beaten
A little honey (optional)
Olive oil
Salt and pepper
Pre-heat your oven to 180c/350f. With a serrated knife slice your tomatoes 5mm or so thick. Lay them out in one layer on a baking tray or large plate and scatter with salt. Set aside for 20 minutes.
In a large frying pan over a medium heat melt the butter and add a dash of olive oil, half the thyme, the garlic and your finely sliced onions. Allow them to cook gently for 10-15 minutes until they’re sweet and lightly golden brown.
Place the pastry on a lined baking tray and spread with the Dijon mustard, leaving a 1cm border around the edge of the pastry. Scatter the sweet onions and garlic on top of the mustard and then sprinkle over half of the breadcrumbs.
Drain off any liquid from the tomatoes and blot the slices with kitchen paper. Arrange them over the onions and breadcrumbs, covering the whole surface (any leftovers can be used in a salad). Brush the edges of the pastry with beaten egg, drizzle the tomatoes with a little honey, then scatter the remaining breadcrumbs and thyme over the top with some salt and pepper and a little olive oil.
Bake the tart in the oven for 30-40 minutes until the pastry is a deep golden brown and the tomatoes are jammy. Serve warm or at room temperature with a green salad and some good cheese on the side.
