In this technique, the background peeking through can be either the star or just in a supporting role.
The concept is to have a background fabric and put the main pieces on it where only part of it shows through. So it's not really pieced or appliqued....it is just...well...peeking through!
Here is an example of the peek-a-boo being a very supporting character. After a long road trip I had gathered a LOT of various kinds of maps (one of the many things I collect!) and wanted to make a piece about road trips, maps, etc. I used the maps with a wonderunder transfer thingie. (Sorry for the technical language there. LOL) The maps became a single piece of fabric.