In a medium bowl, combine the flour, baking powder, and salt. Set aside.

Place the frozen blueberries in a small microwave-safe bowl and heat for about 1 minute until the blueberries are soft. Mash with a fork until they are jam-like. If needed, cool the blueberries in the fridge for a few minutes.

Meanwhile, in the bowl of a stand mixer fitted with the paddle attachment, add the butter and sugar and cream together on medium-low speed until light and fluffy, about 2-3 minutes. Add the cooled blueberry jam and vanilla and beat on medium-high until well combined.

Add the flour mixture and mix until just combined and no flour streaks remain. Fold in the white chocolate chips.

Using a large spring-loaded cookie scoop, scoop a rounded amount of dough (about 2 tablespoons) and place 2 inches apart on the prepared baking sheet. Roll and lightly flatten the top of each cookie.

Bake for 10-12 minutes or until the edges are just set and lightly golden.

Remove from the oven and allow to cool on the baking sheet for 5 minutes before transferring to a wire rack to cool completely.