A bit of a twist on the classic, the elderfashioned gives the drink a bit more of a floral quality. Due to the sweetness of the elderflower, you unfortunately lose out on the classic ritual of the sugar and Angostura, but in return you get a nice change of the classic. I have seen ratios of the ingredients vary from 1:3 to 1:5 with the bourbon being the main ingredient, and personally I find the middle to be just about right.
This is one that will definitely compliment a nice bourbon, and in that case I would probably make it a little stronger and let the elderflower be the compliment to your elderfashioned. As far as garnish goes, orange would probably be best, but lemon adds a nice zest to it as well.
1/2 oz Elderflower Liqueor
1 dash Angostura
Orange twist for a garnish
Stir ingredients in a shaker than strain into a chilled old fashioned glass with ice, top with your choice of garnish.