Cut off about 1cm from the ends of the butterbur stalks and cut them into thirds to make them easier to blanch.

Butterbur Stalk Perilla Seed Soup
A healthy and warm butterbur stalk perilla seed soup recipe that is irresistibly savory.
What You'll Need
Instructions
Boil water in a pot, add one tablespoon of sea salt, then add the butterbur stalks and boil for 6 minutes.
⏱️ 6m 0sRemove the boiled butterbur stalks and immediately cool them in cold water.
Peel the butterbur stalks by starting at the groove and pulling the skin off cleanly.
Cut the peeled butterbur stalks in half lengthwise, then cut them into 4cm lengths.
Soak the cut butterbur stalks in cold water to draw out any remaining bitter taste and toxic substances.
Finely julienne half an onion.
Cut the green onion in half and slice it thinly.
Wash 7 frozen shrimp, remove the moisture, and cut them into quarters.
Pour 800mL of pre-boiled anchovy kelp broth into a pot.
Drain the butterbur stalks from the cold water and add them to the pot with the broth.
Mix 4 tbsp of perilla seed powder and 2 tbsp of glutinous rice flour in 1 cup (200mL) of cold water to prevent clumping, then pour it into the pot.
Add 1 tbsp of minced garlic, the prepared shrimp, butterbur stalks, and sliced onions to the pot.
Season with 1 tbsp of sand lance fish sauce, then add 1/2 tbsp of salt and stir well.
Cover the pot and boil over medium heat for 5 minutes.
⏱️ 5m 0sAdd the sliced green onions and stir.
Add 2 tbsp of perilla oil to finish and boil for a little longer.