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

In a large mixing bowl, whisk together melted unsalted butter, light brown sugar, and granulated sugar until smooth and creamy.

Add the egg, egg yolk, and vanilla extract to the sugar mixture and stir until well blended.

In a separate bowl, whisk together the flour, baking soda, and salt. Gradually add this dry mixture to the wet ingredients, stirring until just combined.

Gently fold in white chocolate chips and frozen raspberries until evenly distributed.

Scoop out 1-ounce portions of dough and place 2 inches apart on the prepared baking sheet.

Bake for about 12 minutes or until edges are golden and centers appear slightly underbaked.

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