1/2 cup fresh mint leaves
4 teaspoons granulated sugar (or 2 packets of Splenda)
1/4 cup fresh blackberries
3/4 cup light rum
1 cup club soda
2 sprigs fresh mint for garnish
1. Place the mint and sugar in a mortar and "muddle" it with a pestle. Squeeze in the lime juice and add half of the blackberries. Lightly crush the berries.
2. Pour the mixture into a cocktail shaker and add the rum and soda. Shake to mix.
3. Place 4 large cubes of ice in two rocks glasses and divide the drink equally between them.
4. Garnish each glass with the remaining blackberries and a sprig of fresh mint.
Now, i tend to prefer this with raspberries instead of blackberries, and I use 7up instead of club soda, so I have to cut back on the amount of sugar used. I've also found that it's a lot less messy if you don't put the soda in until after you've used the shaker. Maybe I've been doing something wrong, but using a shaker with a carbonated beverage seems to be a bit messy. Another important thing to note is that you can just use a spoon and bowl to break up the mint. The important thing is to break it up enough to get the mint oil into the sugar.