Put spinach and water into food processor, and blend.
Mix all ingredients except unsalted butter. Mix at slow speed for 3-5 min, fast speed for 4-6 min until gluten is formed. Add in unsalted butter and mix until well combined.
120g – slightly round it up
Roll out the dough and pipe a line of filling (40g). Fold down the dough to cover the filling and cut strips for the remaining half. Roll down the dough completely. Coat the bottom of the dough with white sesame and place in a mould.