Preheat oven to 350 degrees. Line baking sheet with parchment paper or silicone baking mat and set aside.
In a large bowl, cream butter and sugars together. Stir in egg and vanilla. Whip until light and fluffy. Stir in all dry ingredients until just incorporated.
Carefully stir in chocolate chunks and blueberries.
Scoop onto baking sheet and press down lightly to flatten.
Bake 7-8 minutes or until the edges are golden brown and the centers are soft, but not shiny. Cool 5 minutes on baking sheet and then transfer to cooling rack. Serve or store in airtight container for up to 4 days.