Preheat the oven to 200C/400F/Gas 6.
Place the flour, baking powder, butter, cheese, egg and salt into a food processor and blend together. Add enough milk to form a soft but not sticky dough.
Place the dough onto a clean lightly floured work surface and knead the dough briefly, incorporating the rosemary into the mixture. Using your hands, shape the dough into a disc.
Place onto an oiled baking sheet to bake for 15 minutes, until risen and golden.
Heat the olive oil in a frying pan, add the garlic and cook for one minute. Add the fillet steak and cook until browned on all sides. Remove the steak from the pan.
Add the red wine and reduce the wine by half. Add the beef stock and simmer for five minutes.
Whisk in the butter to give the sauce a good shine, then add the chopped parsley. Add the beef back to the pan and keep warm.
Heat the butter and oil in a frying pan. Add the sliced potatoes and cook over a moderate heat until golden brown and cooked through.
Serve the beef with the potatoes and top with the blue cheese bread to mop up the sauce.