With a mixer beat softened butter and sugar to a cream.
Sea buckthorn wash and place in a blender, grind.
Strain the crushed sea buckthorn through a sieve to the oil-sugar mass and introduce egg yolks. Stir.
Mix flour with baking powder dough.
Sift the flour with baking powder, mix well to avoid lumps. Then add lemon juice. Stir well.
In the dry bowl, beat egg whites with a mixer (5 min) in a solid foam.
With a spoon or spatula gently stir beaten egg whites into the dough (no mixer).
Lubricate the form (24х11) and 3 cookie cutters 9х7 see the softened butter. Put the dough in prepared forms, put in a deep pan. Pour a third of the hot water and bake 40-50 minutes until Golden brown, at a temperature of 180 degrees. Small molds can be removed after 35-40 min.