We have made this a couple of times and it is very popular - and very easy. The recipe below is the standard one and I'll add my adjustments in italics.
For the topping:
12 oz frozen mixed berries, thawed and drained (we like raspberries and blueberries)
3 tb sugar
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For the panna cotta:
vegetable cooking spray
1 tb milk
1 1/4 ts unflavored gelatin
1 1/4 c whipping cream
1/3 c milk
1 tb vanilla
1/4 c sugar (I skimp on the sugar because I'd rather have a less sweet panna cotta)
1/4 c mascarpone cheese
1/4 c sour cream
Chilling time:3-12 hours (I've made this two days in advance with no problems)
Directions Place mixed berries in a small bowl and crush slightly with the back of spoon. Stir in 3 tablespoons sugar. (If the berries are already sweet - or if you can get fresh ripe berries - I decrease the sugar and add some Cointreau or other liquor.)
Cover with plastic wrap and set aside.
Spray four 3/4 cup ramekins with cooking spray. (I use one large serving dish instead of individual ramekins and skip the cooking spray.)
In a small bowl, pour 1 tablespoon milk. Sprinkle gelatin over and allow it to soften (10 minutes).
Meanwhile, combine cream, 1/3 cup milk, vanilla, and 1/4 cup sugar in a saucepan. Bring to a boil over medium high heat, stirring often. Remove from heat, add gelatin mixture and stir until melted. Let the mixture cool. In a medium sized bowl, whisk together mascarpone cheese and sour cream until smooth. Slowly add the hot cream mixture into the bowl, whisking constantly. Pour mixture into prepared ramekins. Chill until cold and set (at least 3 hours and up to 12) Run a small knife around the edge of the ramekins to loosen the panna cotta. If that doesn't work, dip the bottom of the ramekin in hot water for a few seconds. Invert ramekin onto a plate. (I just scoop out a serving of panna cotta into a bowl for each person.) Spoon berry sauce over panna cotta. Serve.
Thanks for the recipe. I really liked it.