Syrups & Cordials
Fill a large basin with water and place an immersion circulator inside. Set the circulator to 135°F. Put all the ingredients in a bowl and stir to combine. Transfer to a sealable, heatproof plastic bag. Seal the bag almost completely, then remove as much air as possible by dipping the bag (other than the unsealed portion) in the water. The counterpressure from the water will push the rest of the air out. Finish sealing the bag, then remove it from the water. When the water has reached 135°F, place the bag in the basin and cook for 1 hour. Transfer the bag to an ice bath and let cool to room temperature. Pass the syrup through a fine-mesh sieve. If any particles remain in the syrup, strain it again through a paper coffee filter or Superbag. Transfer to a storage container and refrigerate until ready to use, up to 4 weeks.