In a large mixing bowl, combine the bread flour, water, and active sourdough starter until there are no dry spots. Mix thoroughly until a shaggy dough forms, then let it rest for 1 hour.

After the resting period, incorporate the salt into the dough. With wet hands, pinch and fold the dough until the salt is fully dissolved.

Perform a series of stretch and fold techniques every 30 minutes for 3-6 hours, or until the dough has doubled in size.

Once the dough has risen, carefully turn it out onto a floured surface and shape it into a rectangle.

Prepare the cream cheese mixture and spread over the dough, scatter raspberries, and fold to encase the filling.

Place the shaped dough in a lightly floured banneton, cover, and let it proof in the refrigerator for 12-24 hours.

Preheat your oven to 450°F (232°C) about 30 minutes before baking.

Carefully remove the Dutch oven, lift the dough from the banneton using parchment paper, and bake for 35 minutes. Remove the lid and bake for an additional 15-20 minutes until golden brown.

Transfer the bread to a wire rack to cool completely before slicing.