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 in a large bowl until light and fluffy, about 2–3 minutes.
04 - Mix in egg, lemon zest, lemon juice, and vanilla extract until well combined.
05 - Gradually add dry ingredients to wet mixture, mixing just until incorporated.
06 - Gently fold in raspberries and white chocolate chips, being careful not to crush the berries.
07 - Drop heaping tablespoons of dough onto prepared baking sheets, spacing about 2 inches apart.
08 - Sprinkle with coarse sugar if desired.
09 - Bake for 11–13 minutes until edges are lightly golden and centers are set.
10 - Cool on baking sheet for 5 minutes, then transfer to wire rack to cool completely.