Blueberries are cleaned of leaves and stems and rinse with water. Dry. The beads of the blackcurrant most easily separated by means of a fork. Branch with black currant be held with one hand and with the other drawing the teeth of the fork in the grains. So will not hurt. Washed and dried. The oven is heated to 180C. Tray size 30h24 cm smeared with melted butter. Sift together flour, salt, baking powder and baking soda. In a large bowl, break the butter and powdered sugar. One by one add the eggs, followed by the oil and vanilla. In the mixture is poured the feta cheese mascarpone and mix well. Less than add flour mixture until it forms a sticky dough. In dough pouring blueberries and blackcurrant. Stir gently. Pour the mixture into the prepared form and smoothed. Bake for 30 minutes until the pastry is golden and the initial rising color. Once removed from the oven leave for 10 minutes to cool and then can be removed from the tray. Cut into squares and sprinkle with powdered sugar.