Excellent, this one really surprised me. The Cognac and Grenadine create an almost cherry like sweet/tart combo that is perfect when paired against the Bourbon. Don't skimp the Peychaud's - it is essential to that underlying sweetness. This is an underrated classic, IMO.
A nice combination that starts with the oakiness from the Bourbon and finishes with the fruitiness of the Cognac. Used a very chilled Gibraltar rocks glass.
I tend to drink my drinks a little too fast. I'm a firm believer in "a warm cocktail is a sad cocktail"! Especially in this case served without ice, this as others state needs a well chilled glass.