Contour with 2 steps, break contour group apart, ungroup all, then Arrange, Shaping, Combine
This will make it so the middle area is "knocked out". If you have a colored background the color will now show through on the background. If you do not want any color, you can change the middle area to white and group, however depending on what your application is, this may not be what you want (IE for pad printing if there's separations, the white may show up).