Put flour, salt, egg yolks and 3 tablespoons of water in a bowl. Spread softened butter on top and work into a smooth dough with the dough hooks of the hand mixer. Wrap in foil and chill for about 30 minutes
Wash the courgettes, grate them dry, clean them and peel 6 nice strips of each courgette lengthwise with a peeler. Coarsely grate the rest of the courgettes, put them in a sieve, sprinkle with 1 pinch of salt and drain. Blanch the zucchini strips for 1 minute in boiling salted water, drain and spread on kitchen paper to dry. Roll out the dough thinly and line a tart dish (26 cm Ø) with lift-off base. Cut off any protruding edges or fold them inwards and press them firmly. Line tart with baking paper and fill with dried peas. Bake the tart in a preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for approx. 10 minutes. Remove baking parchment and dry peas and bake for another 5 minutes until golden brown
Meanwhile grate the Parmesan cheese. Wash the thyme, shake dry and remove the leaves. Cut the goat's cheese roll into 12 equal slices. Peel and finely chop the onion. Squeeze the zucchini rasp. Heat oil in a pan, fry onion until translucent, add grated zucchini and fry for about 5 minutes. Season with salt and pepper
Mix eggs and cream, season with salt, pepper and thyme leaves, leaving some aside for garnishing. Pour the zucchini and onion mixture onto the tart base. Sprinkle with cheese and pour the cream and egg mixture over it. Spread the zucchini strips on top so that a check pattern is created. Spread the goat cheese slices evenly around the edge. Bake in the preheated oven (electric range: 175 °C/ convection oven: 150 °C/ gas: level 2) for approx. 45 minutes until the filling is firm and the cheese is golden brown
Waiting time approx. 15 minutes