In a small saucepan, mix the water with the sugar and salt. Sprinkle the agar powder evenly across the surface of the water. Heat the agar mixture, stirring until the agar is dissolved and the solution comes to a full boil. Pour agar mixture into a cup with a spout (like a Pyrex cup) and let cool slightly for 10 minutes.

Place molds on a baking sheet. If necessary, support the molds with small cups. Pour agar mixture into molds and pop any bubbles with a toothpick.

Refrigerate molds for several hours until solid. Carefully unmold onto plates. Dust with kinako powder, drizzle on the kuromitsu syrup or agave syrup, and serve immediately.