I made this almost by accident. Having set out to make a Hanky Panky as the final cocktail of a weekend full to the brim thereof, I grabbed, instead of the Fernet, the bottle of dirt cheap triple sec that was next to it. I was about to put it back and said "why the hell not" and threw a little in with the standard Hanky Panky ingredients. It was surpisingly delicious. I think it would be even better with a fancier orange liqueur, but can't say for certain.
1.5 oz Gin (used Broker's)
1.5 oz Sweet Vermouth (I believe I used Dolin)
0.5 oz Triple Sec
0.25 oz Fernet Branca
I made this in the glass, because we were almost out of ice. Poured all ingredients over a big ice cube, in a chilled glass stirred for a good long time, twisted a piece of orange zest over the drink, and then threw in a wedge of orange I had sitting around as well (but did NOT squeeze, it was delicious to eat when the drink was done)