Blend fresh or frozen raspberries until smooth, then strain the puree through a fine mesh sieve to remove seeds.

In a small saucepan, gently heat the heavy cream over low heat until it begins to simmer.

Remove the saucepan from heat, add the chopped dark chocolate to warm cream, and let it sit for a minute before stirring until melted and smooth.

Stir in the raspberry puree and vanilla extract until fully blended.

Cover the bowl with plastic wrap and refrigerate for about 2 hours, or until firm enough to scoop.

Use a small cookie scoop or your hands to form small balls from the chilled mixture.

Roll each ball in cocoa powder or crushed nuts until evenly coated.

Return the coated truffles to the fridge for another 30 minutes to set.