Whisk the water, soy sauce, miso, Mirin, sesame oil, rice vinegar and liquid smoke in a small saucepan until well combined. Mix the sugar, cornstarch, spice, and garlic in a small bowl to combine and add whisk into the sauce.
Bring to a boil over medium heat, reduce heat and simmer 2-3 minutes until the flavors meld and sauce thickens.
Store in a glass jar in the refrigerator for up to 3 months.