Wash the black soybeans thoroughly and soak them for at least 5 hours.
Put the soaked black soybeans and water into a blender and blend until smooth.
Blanch the mugwort briefly in boiling water, then rinse in cold water.
Add the mugwort, blended black soybeans, milk, and honey into a blender and blend until smooth.
Pour the mixture into a small saucepan and gently warm over medium heat.
Pour the finished Black Soybean Mugwort Latte into a cup and top with nuts, if desired.