The tart can be served as a starter or as a main course and I always serve a salad of mixed leaves with a simple olive oil dressing to accompany it.


The quality of the puff pastry you are using is really important for a fresh-tasting result that isn’t greasy. I always make my own puff pastry and freeze a few pieces so that I have it to hand when I need it. If you are buying puff pastry, make sure it is made with butter.

The technique used here for creating a tart using puff pastry is one that can be repeated over and over again with other vegetables and fruit. The mushroom in the recipe is one of those big flat mature mushrooms that has dark brown gills rather than the smaller ones with pink gills.

The more deeply flavoured mushroom that I favour here stands up well to the robust flavour of the roasted onions and pairs well with the delicate ricotta. Serves 4

  • 250g puff pastry 
  • 2 medium red onions, peeled and each onion cut into 8 even-sized wedges
  • 2 tablespoons + 2 teaspoons extra virgin olive oil 
  • 2 large sprigs of fresh thyme
  • sea salt and freshly ground black pepper 
  • 100g buffalo or sheep’s milk ricotta
  • 25g Parmesan, grated 
  • ½ teaspoon fresh thyme leaves
  • 1 large flat mushroom 
  • 2 teaspoons fresh marjoram leaves

To serve 

  • salad of mixed leaves


  1. Preheat the oven to 200°C. Line a baking sheet with non-stick baking paper. 
  2. Roll the pastry out and cut into a neat 22cm circle, saving the pastry trimmings for another day. Place on the lined baking sheet. To achieve a rim on the cooked tart, cut another circle 1cm in from the edge of the pastry. Your knife should pierce the pastry about 1mm deep and should be an obvious cut, not just a mark. This 1cm rim will be the risen edge of the cooked tart and will hold the vegetables in place.
  3. Now pierce the pastry inside the 1cm rim all over with a normal table fork, making sure you feel the tines of the fork hitting the baking sheet. Do not pierce outside of the 1cm rim with your fork. The somewhat alarming holes you have created with the fork in the bottom of the pastry will close and reseal when it cooks. Chill the pastry until you are ready to assemble the tart.
  4. Toss the onions in 2 tablespoons of the olive oil, add the thyme sprigs and season with salt and pepper. Tip into a roasting tray and cook in the oven for 30 minutes, until tender. Cool completely. 
  5. Mix the ricotta with the Parmesan, thyme leaves and the remaining 2 teaspoons of olive oil and season with salt and pepper. 
  6. To assemble the tart, spread the ricotta mixture over the base, making sure not to go onto the pastry rim. Arrange the roasted onions on top. Cut the mushroom into slices 1cm thick and place cap side down, stalk side up, in a circle on top of the onions. Season the mushroom slices. If the thyme sprigs still look reasonably respectable, I pop those on top as well as I love their roasted appearance. 
  7. Cook in the oven for 30 minutes, until the pastry is crisp and cooked through. Add a final few grains of sea salt and the marjoram leaves and serve as soon as possible.