Cook asparagus for 1-2 mins in boiling salted water. Drain well and dry on kitchen paper. Group in twos, then roll up in a slice of ham. Mash the butter with some black pepper and the lemon juice. Split rolls down the middle, but don’t cut completely in half. Spread with a little butter, then add an asparagus wrap to each like you would a hotdog. Add a squirt of salad cream, if you like.