A cabbage rose is an actual flower different from the peony. I know the article calls them peonies, and while the structure looks similar, the pictured flower has petals that look very different from the peony I know. The peony has very ruffled petals that have a very irregular scalloped edge. The flowers in your picture look like they have smooth rounded petal edges.
At any rate, Cakes by Design has instructions for a peony at their website
. (on page 28 of the pdf file) They also sell the peony cutters.
Nicholas Lodge has a DVD on making peonies, though he also has the ruffly, scalloped version.
This may be somebody's version of a peony. but the one I see and make most often looks more like the following