Kasu is the left over rice mash from fermented rice and koji during the sake making process and makes a flavorful pickling medium. Kasu can be sourced direct from sake producers or from a Japanese specialty grocer.
6-8 whole small, similarly sized vegetables or similarly sized sliced vegetables
3 cups of sake lees (dry or wet)
3 (2+1) tbsp of sea salt
1 tbsp of sugar
Splash of sake or mirin (if using dry sake lees)
Salt vegetables with 2 tbsp of the salt. Place in a container with a weight on the mix overnight. The weight can be a small plate with a jar of water or some other weight. Rinse and squeeze all excess water out of the vegetable before you proceed with the recipe. In a separate bowl combine sake lees, 1 tbsp salt and 1 tbsp sugar. Mix well. If you’re kasu is dry, add the sake or mirin to moisten. It should be the consistency of a thick paste now. Using a crock, wide jar or rectangular container, spread part of the sake lees mixture on the bottom. Layer the pre-salted vegetables next and then alternate layers of sake lees with the rest the vegetables. The vegetables should be completely covered. Cover container tightly with plastic wrap or parchment paper and place a weight on it. Ferment at room temperature, out of direct sunlight for at least 5 days and up to a year or more! Like other methods of pickling in beds like nukazuke, you can wait weeks, months or years! Be sure to save the Kasu paste for another couple rounds of pickles!
Fish: A delicious cooked dish is Kasu Black Cod. Take the mixture from this recipe and marinate cod filets overnight. Wipe off all excess kasu or it will burn. The same can be done with vegetables like asparagus and other meats and fish.
Kasu Amazake: A quick and easy amazake-esque drink, great for rainy days or night caps. Warm rice or nut milk in a sauce pan. Add 1 tablespoon of Kasu per cup of liquid. Sweeten with honey if desired. Add a touch of sake to enhance the boozy quality.