If you love the tangy sweet-tart flavor of passion fruit, this sauce should live in your freezer. It's a great addition to yogurt, ice cream, fruit salad, whipped cream, champagne, sparkling water, pancakes... you get the idea! It will keep in the refrigerator for up to a week and can be frozen for 3 months.
Combine the sugar and water in a small saucepan and place over medium heat. Cook, stirring frequently, until the sugar dissolves and the mixture reaches a rolling boil. Reduce the heat to medium and add the passion fruit. Cook until the sauce thickens slightly, about 5 minutes. Remove the pan from the heat and cool.
Transfer the sauce to a container, seal tightly and refrigerate until cold.