To begin, make strained yogurt for the filling of your tart. Line a strainer or sieve with a clean fabric or muslin cloth and place on top of a bowl. Pour the yogurt and salt into the cloth and leave to strain in the fridge overnight.
Preheat oven to 200°C and line a baking tray with baking paper.
Unroll the pastry sheet and score a border about 1 cm from the edge. Using a fork, prick the base of the pastry all over and brush the border with egg yolk. Bake the pastry for 10-15 minutes until it begins to puff up and is nearly cooked.
Meanwhile, using a vegetable peeler, peel courgette the to make ribbons.
Remove the pastry from the oven and flatten the base with the back of a spoon. Spread the prepared strained yogurt over the base and arrange the courgette ribbons and cherry tomatoes. Sprinkle over parmesan, pine nuts and thyme.
Drizzle with olive oil, season with salt and pepper and bake for around 10 minutes.
Allow to cool for 5 minutes before slicing up and serving.
