I use an electric chopper, but others have used a pan/hob........so, not sure what to suggest to be honest as I have a method using around 400ml or more with hot water, whizzing it up and then micro'ing it for 40 secs or so...
Do you have a smoothie maker by any chance? That might do?
Or a whisk....
Dont attempt the shaker as it explodes.
Hope someone else can help you.