Delicate osmanthus jelly with floral sweetness and crystal-clear appearance is an elegant dessert. A family recipe with fragrant, fresh osmanthus flavor.
Combine dried osmanthus flowers and 2 1/2 cups water in a saucepan. Bring to a gentle simmer over medium-low heat for 4 minutes to release the fragrance, being careful not to boil vigorously.
While the infusion steeps, place gelatin powder in a small bowl with 1/4 cup cold water. Stir and let bloom for 5–6 minutes until the gelatin softens.
Strain the osmanthus infusion through a fine mesh sieve to remove the flowers. Return the clear liquid to the pot.
Add rock sugar to the hot infusion and stir gently over low heat until fully dissolved. Ensure the heat does not reach boiling to maintain clarity.
Turn off the heat. Whisk in the bloomed gelatin until completely dissolved and the liquid is smooth. Stir in lemon juice for brightness.
Carefully pour the mixture into a glass dish or molds. Skim off any bubbles to keep a crystal-clear surface.
Allow the jelly to cool at room temperature for 20 minutes, then refrigerate for at least 90 minutes (or until set and fully chilled). Serve cold, cutting into cubes or unmold as desired.