Roll the beef blade in the flour and shake off any excess. Place in a shallow frying pan, adding the oil in stages, and cook until browned. Transfer the beef to a casserole pan. De-glaze the pan with the butter and bring to the boil. Pour over the beef
Add the tomato purée, pour in the reduced chicken stock and bring to the boil.
Once boiling, pour into the casserole dish containing the beef. Cover the dish tightly with tin foil and place in the oven. Bake until the beef is tender, about 3 hours.
Once the beef has cooked, allow to cool with the foil still on. Pour some of the mixture into 7.5x5cm (3x2 in) casserole dishes or ramekins 3/4 of the way up.
Increase the oven temperature to 180 C / Gas 4.
Roll out the puff pastry to the thickness of a pound coin and cut to fit each dish. Place on top of each dish, and brush with egg wash.
Bake in the oven until the pastry is golden and well risen and the beef mix is hot in the middle, about 10 minutes.