Slow-cooked beef stroganoff pie recipe

Scatter in the flour and paprika and cook for 2 mins, stirring until the flour starts to brown. Stir in the tomato purée and cook until a sticky paste forms. Return the beef and any resting juices to the casserole, then stir in the mustard and Worcestershire sauce. Gradually pour in the stock, stirring well, and bring to a simmer.