DirectionsPut the cool water in a small bowl.
Sprinkle the gelatin over the water and set it aside to soften for five minutes.
Put the thawed berries and 1/2 cup of the sugar in a blender and pulse until pureed.
Then put a sieve over a large bowl and run the berries through the sieve to remove the seeds.
Carefully heat the softened gelatin in the microwave on low heat until the gelatin has melted.
It doesnt take long; I usually heat the mixture at 5-8 second increments until the liquid clears.
Then stir the gelatin into the raspberries and set the bowl aside.
Put the egg whites into a heatproof bowl (use one that will fit over a pot).
Put some water in the bottom of the pot and bring it to a gentle simmer.
Put the bowl of eggs over the top of the gently simmering water, whisk the egg whites with 1/4 cup of the sugar until they reach about 140 degrees F using a candy thermometer.
Remove the bowl from the heat and use a mixer to whip the egg whites to stiff peaks.
Fold the egg whites into the raspberry mixture.
In the same bowl that you used for the egg whites, whip the heavy cream until it makes stiff peaks.
Fold the whipped cream into the raspberry mixture.
Taste the mousse and add a little powdered sugar, if necessary, to balance the tartness of the berries.
Divide into bowls and chill it or pipe it immediately into small tart shells (or other shells) and chill, or place all of the mousse in an airtight container to chill until ready to pipe into tart shells.
The mousse holds well in the refrigerator for up to two days.
Shown in chocolate cups with shaved white chocolate garnish.
Adapted from Food & Wine.