First season the flour well with salt and black pepper and dust the beef in the flour. Add sunflower oil to a heavy-based oven-proof pot and the colour the beef all over until golden brown. Remove the meat and drain any excess fat.
Now add the vegetables and the bacon to the same pot and colour again until golden. At this point deglaze the pot with the 500ml of wine and reduce by half.
When the wine has reduced add the meat back to the pot and cover with the Guinness. Add the treacle and stock, along with your herbs. Bring this to the boil and skim any impurities from the top. Simmer this in the oven, covered, at 140 degrees Celsius/ gas mark 1 for three hours or until tender. Leave your oven on.
Now to finish the sauce. Carefully pass the cooking liquid through a sieve and into another pot. Put the pot on a medium heat and reduce it by simmering, to concentrate the taste. When the sauce is reduced, taste, then season with salt and pepper. Then add the vinegar.
To thicken the sauce use your beurre manie – melt the butter and add the flour to make a paste then whisk this into the reduced sauce, then boil the sauce until the right texture is achieved. You want it to look slightly too thick. Add the meat back in and then ladle the mix into a suitable pie dish and cook in the oven for a further one hour. Leave the pie to cool.
Roll the pastry to approximately 1cm thickness and roll over the cooled pie mix. You can decorate it whatever way you like. Mix your egg wash ingredients together and using a pastry brush, brush over the pie Put the pie back into the oven at 180 degrees/gas mark 4 for 25-30 minutes.
