Has anyone tried to add coffee to chocolate cake mix to make it like a mocha cake??? If yes, how did it turn out?

Thanks

Yes I have and it is very good. I have made instant coffee with 2 TBS granules and 2 TBS hot water (this is pretty thick) and add it to a chocolate cake mix. I now have a coffee flavored extract that works very well.
One of my husband's favorite cakes is a chocolate cake with a mocha filling. Mocha filling is just chocolate buttercream with the same coffee extract (homemade or store-bought) used instead of vanilla and reg. brewed coffee instead of water. I then frost it with choc. frosting. BIG hit with my mocha-addicted hubby.
Good Luck!

I always add espresso powder... straight or dissolved in a little water. It works in every recipe.