Been really fond of doing infusions with my sous vide set up lately, thinking of recipes for oils, vinegars, booze, yogurt. . . practically any medium I think would benefit from a simple infusion of flavor. Well, how could I help but do so? With sous vide's given ability of maintaining precise cooking temperatures, this task has just become too easy and convenient not to do. Furthermore, this method cuts down steeping time into hours instead of days or even weeks, which the more typical cold infusion method needed.
I've decided to make a simple lemongrass and vanilla infused syrup this time. Fragrant, sweet, yet fresh and a bit citrusy.
Let's start off by bruising some stalks of fresh lemongrass with the blunt side of a knife to release all those essential oils. Chopping would also be another, if not better, option since we'll be filtering our syrup anyway in the end.
Though unnecessary, but more of a cooking habit I developed, bundling up lemongrass stalks just keeps everything neat and organized.
Put your sugar, lemongrass bundle, and vanilla bean pod into a sous vide bag together with a bit of liquid. I've simply added water, but going for fruit juices, alcohol, or soda would all be interesting options.
Seal the bag and leave it for 2 hours in a water bath preheated to 194F.
Though I really think this step is unnecessary, I nonetheless transferred the bag into an ice bath for food safety reasons.
Your syrup would most likely have minute sediments from the vanilla and lemongrass. Filtering it through a fine sieve lined with cheese cloth would easily bring back its clarity.
This should last practically forever in your pantry, ready to serve with anything from pancakes, to toasts, oatmeal. . . any dish that needs a bit of sweet fixin'.