Hi momof4boys - I’ve made Rose’s fondant from TCB. It tastes the way oreo filling used to taste 30 years ago… light, delicous, cool on the tounge, and melts in your mouth. The fondant recipe feels as smooth as babies bottom (you should know that feeling with 4 boys).
Since the printing of TCB, Crisco Shortening has gone “non trans fat”, which people report causes problems with the fondant recipe. One of the bloggers tested Spectrum Organic shortening and found it to be an excellent substitute for the old Crisco formula. I’ve purchased the Spectrum and agree - it works wonderfully. You can find the Spectrum at health food stores, but be prepared for the price.
I’ve never made marshmallow fondant, so I can’t compare the two flavors for you.
As for refrigerating a cake covered in fondant… it’s generally not recommended, but I’ve read there are a few cake makers who do. Check out this thread: