The Boulevardier goes nuclear. I discovered this cocktail thanks to J. E. Clapham of Clapham Cocktails, who says, "This is truly excellent, though it does...
Based off the comments backed off the Campari a bit and increased the bourbon slightly. Used Smith and Black Jamaican Navy Rum and California Redwood Empire Pipe Dream 101 bourbon. Wonder. Perfect for a late night sipper on a cold November night.