1 cup whole milk
1 cup cream
1/2 vanilla bean or 1tsp vanilla essence
tablespoons fresh lemon juice
teaspoons unflavored gelatin
1/2 cup sugar
1 cup yogurt
2 tablespoons grated lemon peel
2 cups blackberries
3 tablespoons brown sugar
2-3 tablespoons crème de cassis
For panna cotta
Lightly oil six ramekins. Mix milk and cream in heavy medium saucepan.
Scrape in seeds from vanilla bean; add bean. Bring to simmer.
Remove from heat. Cover and let stand for 30 minutes. Remove vanilla bean.
Pour lemon juice into small bowl and mix in gelatin. Let stand until gelatin softens for about 10 minutes.
Stir sugar and gelatin mixture into milk mixture. Stir over low heat just until sugar and gelatin dissolve, about 2 minutes.
Remove from heat. Whisk in yogurt and lemon peel.
Divide among ramekins. Cover; chill until set, at least 6 hours.
Puree 2/3 of blackberries, brown sugar, and crème de cassis in blender.
Run small knife around each panna cotta. Place bottoms of ramekins in a bowl of hot water for about 45 seconds.
Invert ramekin, shaking gently, to turn out panna cotta.
Serve with sauce.