Preheat your oven to 350°F (175°C). Line baking sheets with parchment paper.
In a bowl, whisk together flour, baking soda, and salt. Set aside.
In a large mixing bowl, cream together softened butter, granulated sugar, and brown sugar until light and fluffy.
Beat in the egg and vanilla extract until combined.
Gradually add the dry ingredients to the wet mixture, mixing gently until just combined.
Carefully fold in the chocolate chips and raspberries (if using fresh raspberries, toss them in a little flour before adding). If using frozen raspberries, add them directly frozen and fold gently.
Chill the dough for at least 1 hour (up to 2 hours) to prevent spreading.
Scoop dough onto the baking sheets, spacing cookies about 2 inches apart.
Bake for 10-14 minutes, until edges are golden but centers remain soft. Adjust time if using fresh or frozen raspberries.
Let cookies cool on the baking sheet for 5 minutes before transferring to a wire rack to cool completely.