Season the beef rump cap generously with salt and pepper, then rub with mustard seed oil. Arrange on grill over barbecue coals and cook for 20 minutes, turning regularly, until medium. Allow to rest for 3 minutes.
Combine the parsley, oregano, garlic, chilli, vinegar and extra virgin olive oil in a bowl and season with salt and pepper. Mix the radish, asparagus and dragon fruit in a second bowl. Carve the beef and serve with the salad, sauce and grilled bread.