Because I don't know the real name of this technique...
(Yes this is snail plate... because French people eat snails, that's a well-know fact)
The picture is not so good but here is the idea.
This is very simple. You just have to put together pieces of polymer clay this way:
It's easier to cut equal pieces before putting them together as you can compare the proportions the different colors will take. The first color will be the most present.
Then you just have to put everything into your clay extruder and you will get the following:
Roll each yarn on a sheet of clay (here I chose black). I usually prefer starting with the end of the yarn (putting it in the center of the spiral) as it enables to have less of the "main color" and so more different shades.
Flatten your spiral with a roll (be careful not to deform the spiral and to remove all air bubbles if there are some)
Then use your pasta machine (or keep on with your roll). The first time, your spiral is totally deformed but if you put it once again in the pasta machine in the other direction,everything is fine again.
You can then cut the middle of your spiral with a cookie cutter and put it on your snail plate (or anything else you may use for cooking it!)
The colors I chose don't have enough shades but the result of this technique is often great... perfect for hand-made lenses for necklaces or pendants.