Before you pour it into your martini glasses, rub the vanilla bean pods around the lip of the glasses to add an initial taste of vanilla to the drink. Then pour in one oz. of seltzer into each of the two glasses and finally pour the contents of the shaker into the glasses gently on top of the seltzer. Add grapefruit segments last.
Note: I prefer to add segments of citrus when they are cut into what are called supremes (pronounced soo-prems). To do this, take a knife and cut the rind of whatever citrus fruit you are using going from top to bottom in strips. Once the fruit is peeled, cut segments from the citrus in between the white membranes that separate the segments. That's it. Very easy and the juice from a segment cut like this can add more depth of flavor to a drink.