Heat Amasake, juice, agar and lemon peel in a medium saucepan.
Simmer 5 minutes until agar dissolves.
In a seperate bowl, mix kuzu with lemon juice until it dissolves and add to saucepan and stir until it thickens.
Add salt and vanilla.
Cool briefly and pour into individual serving dishes or bowl.
Let set for 1 hour in the fridge before serving.