Mix the flour, salt, margarine, sugar, baking powder, and the egg in a bowl to a pie bottom.
Roll out the dough and cover a pie form with the pie bottom. Pick the bottom a few times with a fork.
Place it in the fridge for minimum 30 minutes.
Start the oven at 210 degrees Celsius.
Whip the egg yellows together with half of the sugar, add the cinnamon and the hazelnut flour and mix it well.
In another bowl whip the egg whites and the salt to a hard foam. Add the rest of the sugar while still whipping.
Pour the egg whites in the bowl with the rest of the ingredients.
Place the filling in the pie form.
Place the pie in the middle of the oven for 10 minutes. Lower the temperature to 175 degrees Celsius and let it in the oven for another 25 minutes.
Take out the pie and let it cool down before serving it.