1. Spray six 3/4-cup ramekins with a light coating of cooking spray. Or prepare panna cotta in a 1-quart serving bowl without cooking spray.
2. Sprinkle gelatin over cold water in a small bowl. Let stand until softened.
3. Heat heavy cream, 1/2 cup sugar and orange zest in a medium saucepan over medium-high heat to just below boiling; stir until sugar dissolves.
4. Remove from heat. Add gelatin mixture and stir until dissolved. Cool to lukewarm.
5. Stir buttermilk and vanilla into cream mixture. Divide evenly between prepared ramekins or pour into bowl.
6. Refrigerate 4 hours or until set. (Can be covered and refrigerated up to 48 hours ahead.)
7. Combine blackberries, Cointreau and remaining 2 teaspoons sugar in a medium bowl. Using the back of a spoon or a fork, gently mash berries, leaving some of the berries whole.
8. To serve, run the tip of a sharp knife around edge of ramekins.
9. Turn out onto serving plates. (Or scoop panna cotta into dessert dishes). Spoon berries alongside or on top of panna cotta.

Lighten Up Tip

1. Lighten up the recipe by replacing the heavy cream with half-and-half or fat-free half and half. (Panna Cotta will be less firm.)