In a bowl, whisk the bean starch with 250ml cold water
Bring 1.1l water to a simmer, lower the temperature, mix the starch mixture again to ensure it’s equally dissolved, then slowly whisk into the hot water. Stir the mixture until it begins to thicken and turns translucent, then continue simmering for 1-2 minutes until it becomes the consistency of a thick sauce that will form ripples on the surface when you drizzle the sauce into itself with a spoon. Pour the paste into a bowl and allow to set for around 4 hours at room temperature
Tip the jelly onto a plate, coat with a little cold water and use a jelly scraper to cut the noodles (or cut into thick noodles of choice with a knife)
Peel the garlic and grate into a small bowl. Add soy sauce, vinegar, sesame oil, sugar and Sichuan pepper to the bowl and mix well. Stir in 100ml cold water and refrigerate for at least 30 minutes. In the meantime, finely slice the spring onions and toast the sesame seeds until golden brown
Place the noodles into a bowl and pour over the cold sauce followed by the chilli oil, sliced spring onion and sesame seeds. Serve cold and enjoy!