1 oz rye whiskey (Rittenhouse, appropriately)
1 oz applejack (Laird's Straight Apple Brandy in this case)
3/4 oz sweet vermouth (Dolin here)
1/2 oz Fernet Branca
1 dash aromatic bitters (Angostura)
Stir and strain into a chilled cocktail glass. Garnish? What's that?
If you want to use a decent Italian vermouth (Carpano Antica or its ilk) you can probably back off to 1/2 oz and possibly omit the bitters, though I haven't tried it this way.