1. In a Collins glass, muddle mint and sugar together gently. Juice lime directly into glass, and stir gently
2. Top glass with ice, and add rum. I like just 1 jigger and a pony, but that's dependent on how you like it.
3. Finish off with the Red Bull or energy drink or seltzer water. Garnish with the lime halves or more mint leaves, and enjoy while thinking you're sitting on a beach in Cienfuegos (or Miami)!