Pre heat a frying pan on medium/high and add approx 15ml rapeseed oil. Fry the onion and carrots for 2 minutes then add in the mushrooms and fry for another 6 minutes, stirring occasionally. Remove from the pan and add the beef, fry until brown all over and add the veg back in. Mix the flour with the mustard powder and sprinkle over the meat and veg, cook for approx 2 minutes, stirring. Add in the rosemary tips that have been picked from the stalks, pour in the beer and add in the puree, ketchup and crumble in the beef stock cube. Bring to a boil and simmer uncovered for 25-30 minutes until the sauce has reduced, stir occasionally. Leave it to cool completely, you can speed this up by putting into a different container.

Once cooled transfer to a pie dish and cover the top with puff or shortcrust pastry, leaving holes for steam or using a pie funnel. Wash with a mixture of beaten egg and milk and bake @ 180c (fan) – 200c (non) for 25-30 minutes, until golden in colour.