Cut the one pound of tenderflake into eighths and add the boiling water. Stir to melt shortening until it is white and creamy with no unmelted lumps. Mix together flour, baking powder and salt and stir the whole amount into the melted shortening. Divide into 4 parts and wrap with wax paper or plastic wrap and put in the fridge for an hour or two. Roll on well floured board and bake as suggested in your tart or pie recipe.