For now I'm using TFA Mocha about 1 drop per ml 1% EM.5% and 2 drops sweetener per 5ml
Not great, but vapable until I can come up with something.
I don't do ground coffee so not going to buy a big can just to try extraction.
With all the Flavors available and all the e-liquids(some decent) it has to be able to be done.
In the coffee aisle of most supermarkets you can get the trial size samples of coffee grounds. A buck or so for the nice ones.
Also some supermarkets have the ground your own by the pound. You can ground a handfull of beans and It sould cost a buck or two instead of 8-10 for a whole can of cofee.