To prepare the Sesame Spinach, wash the spinach leaves and set aside to drain. Grind the sesame seeds until smooth with a mortar and pestle. Heat the sugar, salt, dashi stock, soy sauce and the ground sesame seeds in a large saucepan over high heat. Toss in the spinach, one handful at a time until all the spinach is just cooked. Remove from the heat and drain. Set