Place finely chopped white chocolate in a heatproof bowl. In a small saucepan, gently heat heavy cream and chopped dried blueberries until it just begins to simmer, then remove from heat.

Pour the hot cream mixture over the chopped white chocolate and let it sit undisturbed for 5 minutes to begin melting the chocolate.

After 5 minutes, add butter, vanilla extract, and salt to the bowl; whisk gently from the center outwards until the mixture is smooth, glossy, and emulsified.

Cover the bowl with plastic wrap directly onto the ganache surface and refrigerate for 2-4 hours, or overnight, until firm enough to scoop and roll.

Once chilled, use a small spoon or mini ice cream scoop to portion the ganache, then quickly roll each portion into smooth, round balls between your palms.

For powdered sugar or cocoa powder, roll truffles in a shallow dish until fully coated. For melted white chocolate, dip each truffle using a fork and place on parchment paper to set, sprinkling crushed freeze-dried blueberries immediately if desired.

Place coated truffles on a parchment-lined tray and refrigerate for 15-20 minutes to allow the coatings to fully set.