Step 1: Preheat and Prep

• Preheat oven to 375°F (190°C).

• Line baking sheets with parchment paper or silicone baking mats.

Step 2: Mix Dry Ingredients

• In a medium bowl, whisk together flour, baking powder, and salt. Set aside.

Step 3: Cream Butter and Sugar

• In a large mixing bowl, cream butter and sugar until light and fluffy (about 2 minutes).

• Beat in the egg and vanilla extract until well combined.

Step 4: Combine Wet and Dry

• Gradually add the dry ingredients to the wet ingredients, mixing slowly.

• Alternate adding sour cream with the flour mixture until fully incorporated.

Step 5: Fold in Blueberries

• Gently fold in the blueberries, being careful not to crush them.

Step 6: Shape and Bake

• Drop spoonfuls of dough (about 1–2 tablespoons each) onto the prepared baking sheet, spacing about 2 inches apart.

• Bake for 12–15 minutes, or until edges are lightly golden.

Step 7: Cool

• Let cookies cool on the baking sheet for 5 minutes, then transfer to a wire rack to cool completely.