For the cookies, I made my super-simple sugar cookie recipe (recipe in my new book!), and used a large circular cookie cutter to cut out the shapes. Once the cookies were baked and cooled, I whipped up a batch of royal icing (recipe also in the book!), divided it into three portions, and colored it red and blue (and left the third portion white). Then I used the stiff icing to pipe circles onto my cookies to form Captain America's shield logo.
I thinned out some of the icing, and used that to filled in the gaps with red, white, and blue runny icing. Once that dried overnight, I piped a white star in the middle, filled it in with white runny icing, and once that dried I piped a final white outline on the star.
You'd think it would be super easy since I was just piping circles instead of all the other cookie shapes that I've done, but I'd have to say that it's pretty hard to pipe perfectly round and well-spaced circles! Most of them turned out to be very wobbly circles!