Sift the flour, icing sugar and baking powder into a large bowl. Mix in the salt. Add the vanilla extract and the ghee. Rub it in with your fingers until it is well incorporated with the dry ingredients and forms a stiff (almost crumbly) dough that will hold together when pinched together. If required, add a little more ghee, about a teaspoon at a time till your dough comes together. Do not overwork the dough though.