1. Place the flour with salt & pepper in a plastic ziplock bag and add the cubed meat. Toss the bag so that the flour coats the meat, then remove the meat from the bag.
2. Heat 1 tbsp of oil in a large pot on medium heat. Brown and seal the beef on all sides.
3. In the same pot, fry the onion, carrots and celery stick until soft and golden brown.
4. Add the mushrooms and peas with the garlic and fry for 5 minutes before adding the paprika and herbs.
5. Pour the stock into the pot. Stir to combine everything and reduce the heat. Cover the pot and allow the stew to simmer gently for 1 hour. Give the stew a regular stir and add more stock if necessary.
6. When the meat is tender, remove the lid and let it simmer gently for 20 minutes on a low heat to allow the sauce to thicken and reduce.
7. Preheat the oven to 180°C.
8. Transfer the beef stew to a pie dish then cover with the puff pastry. Brush the pastry with the beaten egg. Cut a slit at the top of the pie for steam to escape through.
9. Place in the oven and bake for 25 to 30 minutes until the pastry is cooked through and golden brown.
10. Remove and allow to rest for 10 minutes before serving.