For the crusted lamb cutlets, place the breadcrumbs, salt and freshly ground black pepper into a mini blender and process until well combined. Dip the lamb cutlets into the beaten egg and then roll in the breadcrumbs.
Heat the olive oil in a frying pan, add the cutlets and fry on both sides until golden-brown and cooked through. Remove the lamb cutlets from the pan and set aside to rest in a warm place.
Add the butter, mint and lemon juice to the pan and simmer together.
For the crushed Roquefort potatoes, place the hot cooked potatoes into a saucepan, add the Roquefort, mint, salt, freshly ground black pepper and cream and crush roughly with the back of a fork.
To serve, divide the crushed potatoes between two serving plates and top with the lamb cutlets. Pour over the mint and butter sauce from the pan and serve.