Basically, a Negroni with bourbon replacing gin. The original 1927 recipe calls for equal parts, but I've previously favoured a 3:2:2 (45ml bourbon, 30ml...
Just made this with 2:1:1 Buffalo Trace Bourbon, Martini, and Campari. Luxardo cherry to garnish, because I felt like it. Served in a cut crystal Old Fashioned tub.