01 - Preheat oven to 350°F. Line two baking sheets with parchment paper.
02 - Whisk together flour, baking powder, baking soda, and salt in a medium bowl. Set aside.
03 - Beat butter and sugar together in a large bowl until light and fluffy, approximately 2–3 minutes.
04 - Mix in egg, lemon zest, lemon juice, and vanilla extract until fully incorporated.
05 - Gradually add dry ingredients to wet mixture, mixing just until flour disappears.
06 - Gently fold raspberries and white chocolate chips into dough, taking care not to crush the fruit.
07 - Drop heaping tablespoons of dough onto prepared baking sheets, spacing 2 inches apart.
08 - Sprinkle coarse sugar over dough mounds if desired.
09 - Bake for 11–13 minutes until edges are golden and centers appear set.
10 - Let cookies rest on baking sheet for 5 minutes, then transfer to wire rack to cool completely.