Take a bowl and tip ¼ lb of unsalted butter (100 gr) into the 1 ⅔ cups of all purpose flour (200 g). Rub them together until the mixture looks like breadcrumbs. Then add ¼ tsp of salt and 5 tbsp of ice water. Knead the dough gently with hand until all the ingredients are fully incorporated. If you have time, leave the pastry in the refrigerator to rest for about 30 minutes to one hour. If not, start working with the pastry immediately.
Roll out the pastry to ⅛ inch (0,3-0,4 cm) thickness on a lightly floured surface, place it carefully in a form and prick it with a fork. To make the crust crunchy before baking place it in the freezer for about 15 minutes.
Meanwhile, preheat the oven at 400°F( 200°C). Cover the base of the pastry with baking parchment paper and then fill it with weight (rice, beans or whatever you have). Place it in a springform baking pan and bake for 15 minutes. Then remove the weight (with parchment paper) and return to the oven for another 5-10 minutes to cook the base of the dough - until the crust obtains a lightly golden colour. When it is done, set the quiche crust aside.
Heat 2 tbsp of olive oil in a large nonstick skillet over high heat. Add 2 crushed garlic cloves and a sprig of thyme. When garlic turns golden brown colour, take them out.
Thinly slice one small leek into rings. Pour it together with mushrooms (if you used dried one - already boiled) in flavored oil and fry, stirring often for 6-8 minutes. Season with some salt and pepper. When vegetables are done, set them aside on a paper towel to cool and to leak excess oil from them.
Grab about 8 oz (200 g) of cheese - I took 2 oz (50 g) of each: parmesan, mozzarella, gorgonzola, and gouda. Grate parmesan and cut in medium size pieces the rest of the cheese.
Take 2oz (50 g) of mascarpone and evenly grease it along the bottom. Then nicely arrange the fried mushrooms and top with pieces of cheese (mozzarella, gouda, and gorgonzola). Sprinkle with grated parmesan cheese. Lower the temperature of the oven to 375°F (180 °C) and bake the quiche for 15-20 minutes, depending on the size of the form!
If your willpower allows, let cool slightly! And enjoy!