Preheat your oven to 350°F (175°C). Line a baking sheet with parchment paper.

Cream the butter and sugar together in a large bowl until light and fluffy.

Beat in the egg and vanilla extract until smooth.

Whisk together the flour, baking soda, and salt in a separate bowl.

Gradually add the dry ingredients to the wet mixture, mixing just until combined.

Gently fold in the blueberries and lemon zest.

Scoop tablespoon-sized balls of dough onto the baking sheet, spacing them 2 inches apart.

Bake for 13–15 minutes, or until the edges are golden.

Cool on the sheet for 5 minutes, then transfer to a wire rack.