Heat the grill. Mix together the butter and garlic puree and season with salt and pepper.
Brush 1 side of the bread with a tablespoon of the butter and place on the grill, butter side down and grill until golden brown; turn over, top with the cheese and grill for 30 seconds longer or until the cheese melts.
Place the garlic bread on a platter and top the cheese with a few thin slices of the beef and drizzle with the parsley oil.
Remove the steak from the refrigerator 30 minutes before grilling. Heat grill to high.
Brush steak on both sides with oil and season with salt and pepper. Place on the grill and cook until golden brown and slightly charred, 4 to 5 minutes. Turn over and continue grilling to medium-rare doneness. Remove from the grill and let rest 5 minutes. Slice into 1/4-inch thick slices.
Mix together ingredients in a small bowl. Season with salt and pepper, to taste.