In a large mixing bowl, beat ¾ cup of softened unsalted butter with 1 cup of granulated sugar using an electric mixer on medium speed until light and fluffy, about 2–3 minutes. Then, add 1 large egg, 1 teaspoon of vanilla extract, ½ teaspoon of salt, and ½ teaspoon of baking soda. Mix until fully combined.

Gradually add 2 cups of all-purpose flour to the butter mixture, mixing on low speed until just combined. If the dough feels too crumbly, slowly incorporate 1 tablespoon of milk at a time until a softer, cohesive texture is achieved.

Fold in 1 cup of white chocolate chips with a spatula and gently incorporate 1 cup of fresh blueberries into the dough, taking care not to crush them.

Preheat the oven to 350°F (175°C) and line your baking sheet with parchment paper. Drop rounded tablespoons of dough onto the baking sheet, leaving about 2 inches of space between each cookie. Bake for 10–12 minutes until edges are lightly golden and centers seem set but slightly soft.

Let the cookies cool on the baking sheet for about 2 minutes, then transfer to a wire rack to cool completely. Store in an airtight container at room temperature for up to 4 days or refrigerate for longer freshness.