Begin by melting the unsalted butter in a small saucepan over low heat until fully liquid, then set it aside to cool for at least 20 minutes.

In a large bowl, combine the cooled melted butter with granulated sugar and light brown sugar, mixing until paste-like.

In a separate bowl, sift together the all-purpose flour, baking soda, baking powder, and kosher salt.

Gradually add the dry ingredient mixture to the wet ingredients, gently mixing until just combined.

Gently fold in the dark chocolate chunks and frozen raspberries with a spatula.

Using a 2 oz ice cream scoop, portion out balls of dough and place them on a lined baking sheet.

Preheat your oven to 350°F (175°C) and bake the cookies for 12-13 minutes.

Allow the cookies to cool on the baking sheet for about 5 minutes before transferring to a wire rack.