In a large mixing bowl, combine your active sourdough starter, room temperature water, and bread flour. Mix until the ingredients come together and form a sticky dough, ensuring no dry flour remains. Cover the bowl with a damp towel and let it rest for one hour at room temperature.

After the dough has rested, add salt to the mixture, ensuring it's evenly distributed. Let this sit for another 30 minutes.

Begin the stretching and folding process by grabbing one side of the dough and stretching it up before folding it back over itself. Repeat this process every 30 minutes for a total of 2-3 hours.

Once your dough is strong and elastic, gently turn it out onto a lightly floured surface. Shape it into a rectangle, then spread the cream cheese mixture and fresh raspberries evenly across the surface.

Transfer the shaped dough into a well-floured banneton or a floured bowl. Cover it with a lint-free towel and place it in the refrigerator for 12-24 hours.

Preheat your oven to 450°F, placing a Dutch oven inside to heat up. Carefully transfer your dough onto a piece of parchment paper. Score the top with a sharp knife or bread lame, then cover with the Dutch oven lid and bake for 35 minutes.

Remove the lid and continue baking for an additional 15-20 minutes until the crust is beautifully golden brown.

Carefully remove the loaf from the Dutch oven and let it cool completely on a wire rack.