Shallot and Prosciutto Pinwheels

What’s an appetizer you can grocery shop for in advance when you don’t have a car because you’re supposed to be moving to Europe in two weeks- Shallot and Prosciutto Pinwheels! Three of us devoured the entire batch of this easy, make-ahead tread on Easter. They were also enhanced with a mustard-horseradish sauce intended for…