If you have lots of stringy bits of glue, a hairdryer on warm will melt those away. (fourseasonfamily.com)
If you have big pieces of spinach pulse it a few extra times so that you get little pieces rather than long stringy bits. (strawberriesforsupper.com)
Also, added the lemongrass at the end -(ground the fresh stalk in a mini food processor until it was completely pulverized, then stirred it in)- for a nice lemongrass punch without hard or stringy bits left in the soup. (epicurious.com)