Choose a 20-25cm frying pan which has a handle that can go in the oven, or a removable handle. Preferably one which is non-stick. Preheat oven to 200°C.

Heat butter and sugar in the pan and stir till sugar has dissolved. Arrange the carrots all over the base of the pan, cut sides down, to cover it completely in a single layer, like a jigsaw puzzle. Alternate wide ends with thin ends so they fit better. Pull thyme leaves off and sprinkle over the carrots then season with salt and pepper. Cook over moderate heat until the carrots are browned underneath and not quite cooked, but starting to soften. If the pan has a lid (or you can find one that fits) you can speed up this cooking process by covering the pan. If the carrots seem to be getting too brown before they're cooked, add a dash of water and continue cooking until it has evaporated.

Cover the carrots with the pastry, tucking in any excess around the edges if it's a square piece of pastry, rather than cutting it off. Bake for 25-30 minutes or until pastry is golden brown. Remove from the oven, stand for 5-10 minutes then invert onto a serving plate.

While the tart is cooking make the whipped feta or goat cheese by whizzing it in a food processor with the yoghurt until smooth, stopping halfway to scrape down the sides. Toast and chop the hazelnuts.

Serve the tart with the whipped feta, thyme sprigs, toasted nuts and a drizzle of chilli oil.