Separately, beat the eggs with the sugar mixer on high speed until fluffy foam.
Combine the butter and flour mixture with the egg and knead the dough.
Distribute the dough in a form (diameter 26 cm), forming low sides, often prick with a fork, so that the dough does not swell when baking. Bake in the oven, preheated to 180 degrees, 15-20 minutes until Golden.
Next, prepare the filling. In a saucepan with a thick bottom, pour sugar. Turn on the medium heat, do not stir it, otherwise it will crystallize.
After most of the mixture becomes runny, you can start stirring it a little, but it is better to just tilt the pan from side to side, so that the future caramel does not burn.
Then add the caramel brought to a boil (!!!) cream, butter, salt and hazelnuts. Stir.
Pour the filling into the sand base, let it cool at room temperature and put it in the refrigerator for 3 hours.