This is the only Guava Martini on the internet. If this isn't the one, do you
remember any of the ingredients?
http://www.barnonedrinks.com/recipes/cocktails/p/pureguavamartini.html
Pure Guava Martini
8 oz. Vodka
4 oz. Guava Juice
2 oz. Raspberry Liqueur
Juice of 1/4 Lemon
Blend with several ice cubes until completely smooth. Serve in a well chilled
martini glass and garnish with fresh raspberries and sprigs of mint.