In a saucepan, combine the osmanthus syrup, jelly powder, water, and sugar (if needed). Stir well until evenly mixed. Heat over medium heat, stirring frequently, and bring the mixture to a boil according to the jelly powder's package instructions.
Remove from the heat and strain through a fine-mesh strainer to remove the osmanthus flowers and any undissolved particles. Carefully pour the mixture into your desired jelly molds and add a few tiny osmanthus flowers to each mold for a beautiful finish. Let the jelly cool until no longer hot, then refrigerate until completely set and chilled. Gently unmold and serve cold.
Notes
Mix the ingredients before heating – Stir the jelly powder, osmanthus syrup, and water together while the mixture is still cold. This helps the jelly powder dissolve evenly and prevents lumps from forming.
Keep stirring while cooking – Stir frequently over medium heat to prevent the jelly powder from sticking to the bottom of the saucepan. Make sure the powder is completely dissolved before removing it from the heat.
Adjust the sweetness – Osmanthus syrup already contains sugar, so taste the mixture before adding more. If you're using dried osmanthus flowers instead of syrup, you'll need to add sugar to taste.
Strain for a clearer jelly – Pour the cooked mixture through a fine-mesh strainer to remove the osmanthus flowers and any remaining particles. This helps create a beautiful, translucent jelly.
Save a few flowers for decoration – Add a few tiny osmanthus flowers to each mold after pouring in the jelly mixture. Let them float naturally for a pretty floral finish.
Work quickly when pouring – Some jelly powders begin setting as they cool, so pour the mixture into the molds while it's still warm and liquid.
Chill before unmolding – Allow the jelly to set completely in the refrigerator before gently removing it from the molds. This helps the jelly hold its beautiful flower shape.