2 oz rye whiskey (if you can't find a straight rye, you can always go for a blend that's got a lot of rye in it: Canadian Club's probably your best bet, and it's usually not priced too high, either)
1/2 oz Italian (sweet and/or red) vermouth
1/2 oz French (dry and/or white) vermouth
1 dash Angostura bitters
1 dash orange bitters
Stir it all briskly with ice and strain into a chilled cocktail glass. Garnish, if you must, with a twist, or, only if absolutely unavoidable, with a cherry.
I prefer the Perfect Manhattan to the classic (which uses twice the Italian vermouth and none of the French) because otherwise it tends a little too much towards the sweet for my liking. In fact, I used to make it with only the French vermouth, and preferred that even to this, but that's not a Manhattan at all...in fact, I'm not entirely sure what that is. It's almost a Brooklyn, but it lacks the maraschino liqueur and Amer Picon. I suppose we could call it a "Five Points"... I also use two kinds of bitters just because I'm indecisive; the old Waldorf-Astoria in NYC (it stood where the Empire State Building is now) used orange bitters, Angostura bitters are traditional, and I like both kinds. So there.
Anyway this drink pits the smokiness of the bitters against the sweetness of the vermouth and the spiciness of the rye. It's a venerable drink, going all the way back to 1874 or so, but while it's drifted in and out of favor (it was rather too flavorful for the Men in the Grey Flannel Suits, who eschewed it for the comforting blandness of the vodka martini) it's lately been creeping back in to the limelight. It's still not a huge mover, but it's good to see it getting the attention it deserves after all these years.