None of these answers are getting to the point. But it is tricky. Sooner or later you're going to have to cross the friendship line. If you just ask him out for a drink, it may not occur to him that you are interested in romance and you end up having drinks with a buddy. Try testing the waters at home in front of the TV, a game or something you both like. Casually just reach out and put your hand on his shoulder. See what happens. If he leans into it or puts him hand on yours, or otherwise reacts positively, look him in the eye and ask if he'd like to go on a date. (I suggest you not immediately jump him.) Take it slow. You wouldn't want to screw up your friendship. And it might take him a while to adjust his thinking... or... he may be thinking that way, too. Or not. If he appears uncomfortable, just say "Sorry, man. You just looked so fucking cute sitting there. We're cool."