Preheat oven to 350°F (175°C). Line two large baking sheets with parchment paper.

In a medium bowl, whisk together the flour, baking soda, and salt. Set aside.

In a large bowl, cream the softened butter, brown sugar, and granulated sugar together on medium speed until light and fluffy (about 2 minutes).

Add the egg and vanilla extract to the butter mixture and beat until well combined.

Gradually add the dry ingredients to the wet ingredients, mixing on low speed until just combined. Do not overmix.

Gently fold in the white chocolate chips using a spatula.

Very carefully fold in the raspberries. If using fresh, be gentle so they don't break too much. If using frozen, work quickly.

Scoop roughly 2 tablespoons of dough per cookie onto the baking sheets, spacing them 2 inches apart.

Bake for 10-12 minutes, or until the edges are lightly golden but the centers still look soft.

Allow cookies to cool on the baking sheet for 5-10 minutes to set, then transfer to a wire rack to cool completely.