Pies always impress and excite. They offer an element of surprise, rather like opening a present. This potato pastry is a good way to use up leftover mashed potato, and it is also delicious.
Melt the butter and oil in a heatproof casserole over a medium heat. Add the paprika and stir for 1 minute, then add the chopped pepper, garlic, mushrooms and lamb. Using a wooden spoon, stir to coat them with oil, then remove from the heat and stir in the flour. Gradually add the milk and soured cream, then stir in the mustard and sugar. Add a sprinkling of salt and stir until smooth. Put the casserole back on top of the stove and bring to the boil, stirring all the time as the liquid thickens. When bubbling, cover and transfer to the centre of the oven.
Meanwhile, make the pastry. Sift the flour, baking powder and salt into a bowl. Cut the butter into small pieces and rub it into the flour until the mixture resembles breadcrumbs. Work in the mashed potato by hand and knead slightly until you have a smooth dough. Form it into a ball, wrap in cling film and leave in the fridge for 30 minutes.
© 1997 Josceline Dimbleby. All rights reserved.