These ham and cheese pinwheels look like they took time and effort, but the little secret is there's only four ingredients! As for the skill level required, if you can make a sandwich, you can assemble this appetizer. Simply roll out some puff pastry, slather on some mustard, sprinkle some cheese and ham, roll the whole thing into a log, then slice and bake. The bacon and cheese crisp up, and the puff pastry becomes as flaky as a croissant. It's the next best thing to being at a bakery in Paris. If you're transporting your appetizer to another house, simply pack up the chilled pinwheel log, and slice and bake when you arrive.