Silky milk-and-cream panna cotta with fresh litchi and rose, set with agar-agar. No gelatin. Make ahead in cups and garnish with pistachio and dried rose petals.
Peel and deseed the litchis. Chop into small pieces (roughly pea size).
Spread on a plate lined with paper towel. Drain 10 minutes while you start the base. Reserve juice for another use.
Bloom and simmer the base
Pour ¼ cup cold milk into a small bowl. Whisk in agar-agar powder. Let sit 5 minutes.
In a medium saucepan, combine remaining milk, cream, sugar, salt, and cardamom if using. Heat over medium-low, stirring, until sugar dissolves and small bubbles appear at the edges (do not boil hard).
Pour the agar mixture into the pan. Whisk constantly. Bring to a very gentle simmer on low and cook 2 minutes until agar dissolves fully.
Pour through a fine mesh sieve into a bowl or pitcher for a smooth set.
Fold, pour, chill
Cool the base 8 to 10 minutes until warm, not hot. Stir in rose water, rose syrup if using, half the dried rose petals, and drained litchi.
Divide among six dessert cups or ramekins. Press a few litchi pieces near the top if you like.
Refrigerate at least 4 hours, or overnight, until set with a soft wobble.
Serve
Top with finely chopped pistachios and remaining dried rose petals just before serving.
Notes
Too vigorous a boil can weaken the agar set. Keep a low simmer for two minutes after the agar goes in.Canned litchi works in a pinch if rinsed, drained, and patted very dry. Fresh litchi gives the best texture.Start with 1 tsp rose water. Add rose syrup only if you want more blush and flavor.Cups keep covered in the fridge up to 2 days. Add pistachio and petals the day you serve.If the set is loose, warm gently, whisk in ¼ tsp more agar dissolved in 2 tbsp milk, simmer 1 minute, strain, and rechill.