Instructions
Muddle the mint sprig and sugar in the bottom of a julep cup. Try to muddle the mint stems and not the leaves so much. Fill cup three quarters with finely crushed ice. Add bourbon. Stir for 30 to 45 seconds until the outside of the cup frosts. Top with more crushed ice. Stir 15 to 30 seconds more. Cup some more crushed ice into a dome over the drink. Garnish with a sprig of mint and use a straw that is cut so only two inches of it protrudes from the ice.
Notes
You can substitute a rocks glass or a highball glass for the julep cup. If you want to be authentic, though, use a silver julep cup. It frosts quite nicely.
The idea behind the sprig of mint and the straw is so you get a heavy dose of mint aroma while you enjoy this drink. Burying your nose in the mint as you sip from the straw is one of life's finer pleasures.
Some recipes call for the mint to only be used for a garnish. Mint flavored syrup is used instead. I like the mint in the drink. If you do use mint syrup, try making your own. Just make a simple syrup and steep mint leaves in it for 10-20 minutes. The more mint the better.
I use Basil Hayden bourbon in my juleps. I had a Mint Julep at the Peabody Hotel in Memphis and they used Basil Hayden. This julep was one of the best I've ever had.