Hi there!
I make coffee dusted steak all the time, (and have even done octopus, bluefish and more), and keep it super healthful and simply by doing just the following:
1. Coat the meat in freshly ground coffee grinds (as a dry rub);
2. Grill as you like.
3. Once off the grill, mop that well, (both sides), through a plate of olive oil, and then put coarse, gray sea salt on it.
That's it.
And they are out of this world!!!!
Cheers! - Leah