1. Preheat oven to 350°F (175°C) and line a baking sheet with parchment paper.
2. In a bowl, whisk together flour, baking soda, and salt.
3. In a separate bowl, cream butter and sugar until light and fluffy.
4. Add egg, lemon zest, lemon juice, and vanilla extract, mixing well.
5. Gradually mix in dry ingredients until just combined.
6. Gently fold in blueberries and white chocolate chips if using.
7. Scoop tablespoon-sized dough onto the baking sheet.
8. Bake for 10-12 minutes, until edges are lightly golden.
9. Cool on the pan for 5 minutes, then transfer to a wire rack.
10. Enjoy warm or store in an airtight container.