Spinach with Sesame Miso Sauce

Japanese Ingredient Substitution: If you want substitutes for Japanese condiments and ingredients, click here.

Gather all the ingredients. Bring a big pot of water to a boil. [Optional] If your sesame seeds are not toasted/roasted yet, or if you want more toasty taste/fragrance, put sesame seeds in a frying pan and toast them on low heat. When 2–3 sesame seeds start to pop from the pan, remove from the heat.
While waiting for the water to boil, add 1 Tbsp mirin to a small saucepan. Cook it over medium heat until the alcohol is evaporated, roughly 30 seconds. Set aside.
In a suribachi (mortar), add 2 Tbsp toasted white sesame seeds and grind with a surikogi (pestle) until the sesame seeds are almost ground. It’s nice to leave some texture.
Add 2 tsp miso, 1 tsp sugar, the alcohol-free mirin, and ½ tsp soy sauce and mix well together.
Once water is boiling, add ¼ tsp Diamond Crystal kosher salt. Hold 6 oz spinach leaves so you can start blanching from the stem (which takes longer to cook). Cook for 15 seconds. Let go the leafy part and cook for 30 seconds.
Remove spinach from the water and soak in iced water to stop the cooking. Alternatively, drain and run the spinach under cold running water until cool.
Collect the spinach and squeeze the water out.
Cut the spinach into 2-inch (5-cm) lengths and add to the bowl.
Mix the spinach and sauce together. Serve at room temperature or chilled.