2 cups (250 grams) all-purpose flour½ teaspoon baking powder½ teaspoon kosher salt¼ teaspoon baking soda1¼ cups (175 grams) fresh blueberries, divided1 cup (227 grams) unsalted butter, melted and slightly cooled¾ cup (150 grams) granulated sugar4 teaspoons (8 grams) lemon zest1 large egg (50 grams), room temperature1 large egg yolk (19 grams), room temperature½ teaspoon vanilla extractSparkling or turbinado sugar, for sprinkling
Preheat oven to 325°F (170°C). Line baking sheets with parchment paper.
In a medium bowl, whisk together flour, baking powder, salt, and baking soda.
In a small bowl, mash ½ cup (70 grams) blueberries.
In a large bowl, whisk together melted butter, granulated sugar, and lemon zest until well combined. Add egg and egg yolk, and whisk until well combined. Whisk in vanilla. Add flour mixture, and whisk just until dry ingredients are moistened. Using a rubber spatula, fold in mashed blueberries and ¼ cup (35 grams) whole blueberries.
Using a 3-tablespoon spring-loaded scoop, scoop dough (about 50 grams each), and place 3 inches apart on prepared pans. Top with remaining ½ cup (70 grams) blueberries, pressing into dough as desired. Sprinkle with sparkling or turbinado sugar.
Bake until golden brown, 18 to 22 minutes, rotating pans halfway through baking. (Dough will spread.) While cookies are still hot, gently swirl a 4- to 5-inch round cutter in a circular motion around each cookie to create an even round. Let cool completely on pans on wire racks. Store in an airtight container for up to 3 days.