I melt it in a coffee cup. not a flat bottom one, but one that gets narrower on the bottom. if that makes sense. Then I take a whisk and roll it back and forth between my palms really fast. My hubby teases me, cause I look like im rubbing 2 sticks together to make a fire. lol. but since MP hardens as soon as it is cool you have to watch it very closely. if it gets hard or too thick melt it a few secs and whip up slightly.
Ive tried this as well for coffee foam on top of a "latte", and found that it you add just an itty bit of citric acid ( say 1/4 teaspoon to 1 LB MP), it keeps it from re-hardening as much.. it will have a softer more pliable consistency longer and gives you a bit more time to play with it.