Making your own passion fruit syrup is a simple matter of adding equal parts (say half a cup) sugar and water along with the pulp of about three passion fruits to a sauce pan and heating for about five minutes until the sugar dissolves. Let it bubble for a couple of minutes to thicken, then turn the heat off and leave it to sit for up to a few hours to infuse. Then simply strain the fruit out. You're left with a flavorful sweet, tart syrup.