It's easy to infuse sugar syrup with whole spices or even herbs. Whole cardamom, cloves, vanilla and star anise all make good flavour pairings with rhubarb. Simply add the chosen spice or herb to the sugar syrup as it comes to the boil.
Different flavours can also be introduced by tweaking the type of sugar used in the syrup, or by substituting water for other flavoured liquid. For example, Anna Hansen poaches rhubarb in 250ml orange juice with 80g Demerara sugar. Bear in mind, though, that substituting water for orange juice will change the sugar level in the syrup which is why ratios may need to be tweaked.
Rhubarb can also be made in a sous vide machine. Seal the sugar, water and rhubarb in a vacuum bag and cook the rhubarb at 60°C for 20 minutes.
