Soften the butter and put in a bowl. Add the remaining ingredients and, using a fork, mix everything together. Check the seasoning; add more Tabasco or salt if required.
Form the butter in a sausage shape on a sheet of greaseproof paper. Roll up, twist the ends tight and chill for at least 2 hours to firm it up.
For the potatoes, heat the oven to 200C/fan 180C/gas 6. Cut the potatoes into wedges. Put a large heavy roasting tin on a medium heat and pour in a generous amount of olive oil.
When the oil is hot, carefully add the potato wedges, rosemary and garlic. Season well with sea salt and mix everything together. Transfer to the oven and cook for a least 1 hour until cooked through. Every 20 minutes, turn the potatoes so that they crisp up all over.
For the steaks, heat a cast iron griddle pan or heavy frying pan- or, even better, fire up the barbecue. Season the steaks with salt and pepper and brush lightly with the oil. Grill for 3-4 minutes each side, for medium rare and to give a good brown crust with distinctive grill markings. Transfer to a plate and rest in a warmish place for at least 5 minutes.
To serve, put a steak on each plate. Unwrap and slice the butter and put a good-sized slice on each steak. Serve with the potato wedges and a green salad.View more Beef recipes...