The grind flour with butter into crumbs. Add salt, yolk and begin to knead the dough, adding as needed cold water. Gather dough into a ball, wrap in plastic wrap and refrigerate for 30 min.

Thinly slice the onion into half rings. Grease the bottom and sides of baking dish with olive oil. Put the onion, then put the pieces of butter, close with a double layer of foil and place in a preheated 200°C oven for 30 min.

Roll out the dough on the working surface in a layer thickness of 0.2-0.3, see Move it on the rolling pin in a baking dish with a diameter of 24-26 cm Gently lay in shape, to form bumpers. Excess dough is cut. Prick bottom with a fork.

Remove the form with the onions from the oven, open and stir thoroughly with spatula, scrape from the walls of adhering pieces of onion. Return onion to the oven, again tightly closed, at 16-17 minutes. In the process of baking mix again (convenient to combine with the process of baking a sand base).

Over the dough place 4 layers of cling film, sprinkle it on rice or barley cereal. Wrap the corners of the film to the center. Bake in preheated oven 10 minutes. Then carefully remove the load and keep in the oven for another 6-7 minutes until Golden brown. Allow to cool slightly.

Remove the dish with the onions from the oven and place on a low heat. Cook, stirring, 15 min. to Watch that the onions don't burn. You should not remain liquid and at the bottom should form a thin crust – brown, but not burnt. Pour in the onion dry white wine, viparita below the crust is formed again. Bow to this moment must purchase a Golden brown color and delicate caramel flavor.

In the slightly cooled shortbread basis put onion stuffing. Sprinkle with cheese. Whisk the egg, milk, sour cream and spices. Spread the creamy filling over the filling and sprinkle some more cheese and then the chopped Basil leaves

Preheat the oven to 190C., bake for 15-20 minutes or until Golden brown. Allow to cool slightly, remove tart from the mold. Serve warm. Delicious mood!