I perfected this recipe over the last holiday, and thought I should share. In 1 glass. Put 4 to 6 mint leaves (less if big, more if small) in glass with a little bit of crushed ice. Grind into a moderate pulp by hand with a big plastic spoon. When ice is slightly green, it's enough. Squeeze juice of 1/2 lime into glass. Pour 3 oz of mineral water (not carbonated water, sparkling mineral water). Add 2 oz of clear rum (cheap works great too!! aristocrap!!!) Add 1 to 2 oz of simple syrup (depends on your taste, I like 2) Pour with strainer into glass half filled with ice. Top off glass with mineral water and stir once. Put spent lime half into glass and enjoy. All our friends love this, and it's quite simple. Sugar may be adjusted to your taste, some like it sweeter, some don't Tastes kinda like minty sprite!!! and the virgin version is quite good as well. Also, it can be scaled up once you get the hang of things, but that requires tasting and adjusting as needed. After 3 or 4, they get even better.