It's called Layered Heat Embossing.
I had to watch a tutorial to make sure I understood what I was trying and then being asked to create a project with the technique.
I used all current Stampin' Up! supplies but let me just say it's tough to layer heat embossing with all you have to work with would be the following embossing powder colors:
I used Cherry Cobbler, Clear and Iridescent Ice although the photo may not show it I did. :)
I have used the technique on the wreath.
The first layer is using the Mint Macaron ink and embossing in clear embossing powder.
The second layer is Cucumber Crush ink with Iridescent Ice embossing powder.
The last layer is using VersaMark ink with Cherry Cobbler embossing powder.
This is a great technique but wish that I could have done something similar to what Wendy did with the butterfly and using different color embossing powders.
Here is a close up that you can hopefully see the different layers.