01 - Combine raspberries, sugar, and lemon juice in a small saucepan. Cook over medium heat, stirring constantly, until raspberries completely break down and mixture thickens, approximately 5-7 minutes. Press through a fine-mesh sieve to remove all seeds. Allow to cool completely before proceeding.
02 - Place 10.5 oz white chocolate, heavy cream, and butter in a heatproof bowl. Set over a pot of simmering water to create a double boiler. Stir continuously until completely melted and smooth. Remove from heat, then stir in vanilla extract and 2 tablespoons of the cooled raspberry sauce. Reserve remaining raspberry sauce for another use.
03 - Cover the white chocolate mixture and refrigerate for 1-2 hours, checking periodically, until firm enough to scoop but still pliable for rolling.
04 - Line a baking sheet with parchment paper. Using a tablespoon or small cookie scoop, portion out the chilled ganache into 24 equal pieces. Roll each portion between lightly greased palms to form smooth balls. Arrange on the prepared baking sheet and freeze for 30 minutes to firm.
05 - Melt 5.25 oz white chocolate for coating. Working with one truffle at a time, use a fork to lower each ball into the melted chocolate, ensuring complete coverage. Lift and tap fork against bowl edge to remove excess coating. Return to parchment paper. Immediately sprinkle tops with crushed freeze-dried raspberries while chocolate remains wet.
06 - Refrigerate completed truffles until chocolate coating is completely set, approximately 20 minutes. Transfer to an airtight container and store chilled. Bring to room temperature 10-15 minutes before serving for optimal texture.