Roll the outside of the beef in the crushed black pepper.
Heat a frying pan on a high heat - add a little olive oil, then brown the meat all over. Remove the beef from the pan. Place the onion rings in the bottom of a roasting tray (this will just keep it from the direct heat ) and the rosemary.
Place the halved garlic bulb on a sheet of foil, season and drizzle with olive oil. Wrap in the foil then place in the roasting tray.
Roast the beef for 12 mins per 450g for medium-rare, or 15 mins per 450g for medium-well.
Whilst the beef is cooking fry the sliced onions in a frying pan with a little olive oil until lightly golden brown.
When browned place them in an oven proof dish then place the halved tomatoes on top. Scatter with thyme leaves and drizzle with olive. Season with salt and pepper.
Place the dish in the oven and back for 1 hour 15 mins.
Remove the beef from the oven, lift onto a platter, cover lightly with foil and rest for 30 mins.
Mix together the breadcrumbs and parmesan and after 1 hour scatter over the tomatoes. Cook for a further 10 minutes.
Take the garlic out of the foil and remove the roasted cloves. Place in a pestle and mortar and mash to a puree. Add the crème fraiche and seasoning. Place in a serving bowl.
Boil the potatoes in salted water until tender then drain. Stir in the butter, parsley and seasoning.
Serve thin slices of the rested beef with the tomatoes, garlic cream and new potatoes.