These are the only recipes I know of for an Appletini.
http://www.keepinitsimplebaby.com/pages/cocktailpages/Appletini.htm
Appletini
3/4 oz apple liqueur
3/4 oz vodka
Splash sweet & sour
Glass: chilled martini
Garnish: apple slice
Shake and strain
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Appletini
2 oz. Sour Apple Schnapps
1 oz. Vodka
Dash of Sweet and Sour Mix
Shake with ice and strain into a cocktail glass.