Start by making the dough. Knead butter, flour and salt together with you hands until a dough forms. Add some water if needed. Form a ball out of the dough, cover it with plastic wrap and put in the fridge. You can alternatively also use store bought dough pastry.
Preheat the oven to 200 Celsius/ 400 Fahrenheit degrees.
Meanwhile prepare the veggies. Cut the butternut squash and zucchini into small cubes. Chop the onion. Heat the olive oil over medium heat in a pan. Add the onion and sauté for a minute. Add the butternut squash and 3 tbsp water and sauté for another 10 minutes (or until the sqush feels almost cooked). Set aside.
In a bowl mix all filling ingredients together: onion and squash, zucchini, crème fraiche, egg, grated cheese and spices.
Take the dough from the fridge and save a small piece (size of one egg) for Halloween decoration if you want. Place the rest of the dough in a pie tin and using your hands press it evenly on the bottom and sides. Bake just the pie crust in the oven for 5 minutes.
Take the pie crust out of the oven and spread a thin layer of tomato puree on the bottom. Spread the filling evenly on top.
If you want to make the Halloween decoration, roll the rest of the dough and cut a pumpkin face with the help of a knife. Place the decoration on the filling.
Bake the quiche in the oven for another 25 minutes.
Let the pie cool down for a while before serving.