In a large bowl, mix the sourdough starter with warm water until it's well dissolved.

Add the bread flour and mix until there are no dry spots. Cover and let the dough rest for 1 hour. This rest period is known as autolysis and it helps the flour to absorb the water, beginning the gluten development process.

After the rest period, add the salt and knead the dough until the salt is well incorporated.

Add the dried fruits, toasted nuts, and orange zest (if using), and knead again until they are evenly distributed in the dough.

Perform a series of stretch and folds every 30 minutes for the next 2 hours. This helps to strengthen the gluten structure of the dough.

Cover and let the dough rise at room temperature until it's roughly doubled in size. This could take anywhere between 4-8 hours depending on the strength of your starter and the room temperature.

Once the dough has doubled in size, gently shape it into a round loaf.

Place the shaped dough into a well-floured proofing basket or bowl, cover it, and let it rise again for about 1-2 hours, until it's puffy.

Preheat your oven to 475F (245C) with a Dutch oven inside.

Carefully transfer the loaf into the preheated Dutch oven, then score the top of the loaf with a sharp knife.

Cover and bake for 30 minutes, then remove the lid and bake for another 20-25 minutes, until the loaf is golden brown.

Let the bread cool for at least an hour before slicing and serving.