For the dough: mix the egg yolks in a bowl with a pinch of salt and sugar
Pour in the melted butter and mix everything into a homogeneous mass
Add the flour mixed with baking powder and knead the shortbread dough.
Divide it into two unequal parts:
Put 2/3 of the dough in the refrigerator for 20 minutes
1/3 put in the freezer for 20 minutes
For the filling: beat the whites to soft peaks, adding sugar. Add the lemon zest and juice.
Add sour cream and mix everything with a mixer in a fluffy mass. Then add the flour and beat again with a mixer
Remove 2/3 of the dough from the refrigerator. Spread on 5 molds with a diameter of 10 cm, forming the sides.
Fill the molds with the filling. Shake the molds slightly so that the filling is evenly distributed.
1/3 of the dough from the freezer grate on top of the filling.
Place the molds on a baking sheet and place in the preheated oven.Bake at t=150-160°With about 20-25 minutes. Be guided by your oven. Determine the readiness as follows: slightly shake the mold, the filling should spring. Try not to raise the temperature too much so that the filling is baked. It is better to raise the temperature at the end of baking and brown the pies.
When baking, the middle will rise, then fall to the previous level. Cool the pies to room temperature to allow the filling to stabilize.