Find some yellow clay or gray fire clay
Mold like modeling clay some what and pack around potato
Cover potatos completely to about half an inch thick. I tried a bowl while I was at it
Carefully lay potatos into coals
I gave them 45 minutes just to make sure. These potatos were small so 20 minutes to a half hour would have been enough
I put on a pair of cotton gloves OUCH that wasnt enough so I used my shovel. These babies were HOT.
Now just tap gently with the back of your knife or multitool and the mud will break off and enjoy.