Riddles

Discovered in Africa, I spread like a tide to become a hotstaple known the world wide. A necessity to some, a treasure to many, I'm best enjoyed amoung pleasant company. Some like me hot and some like me cold. Some prefer mild, others only bold. Some take me straight, while some savor my essence to which has been added a flavor. So put down your cares and sit awhile with me; I'll send you back refreshed and full of energy. What am I?