Preheat the oven to 350°F (175°C) and line a baking sheet with parchment paper.

In a skillet over medium heat, melt the salted butter and brown it for 3–4 minutes until golden and nutty.

Whisk together the browned butter and both sugars in a large mixing bowl until smooth and creamy. Add eggs and vanilla extract, mixing well.

In another bowl, combine all-purpose flour, baking soda, and kosher salt. Gradually stir this dry mix into the wet ingredients, until just combined.

Fold in the chopped chocolate chunks and raspberries gently with a spatula.

Using a cookie scoop, drop rounds of dough onto the prepared baking sheet, leaving space between each.

Bake for 8 minutes, then rotate the sheet and bake for an additional 2–3 minutes until edges are set.

Cool the cookies on the baking sheet for 5–10 minutes before transferring to a wire rack. Sprinkle with flaky sea salt if desired.