Beat butter and icing sugar with an electric mixer till pale and fluffy; add egg and vanilla while beating. Add flour, baking powder and salt to the mixture and mix well. Press the dough in the cooking tray, and put it in the oven.
In a pan heat the butter and add Halawa El Rashidi El Mizan, stir till they melt then pour the filling in the tart and leave till it cools. Garnish with whipping cream