In a large mixing bowl, combine 3 cups of flour, 1/2 cup active sourdough starter, 1.5 cups lukewarm water, and 3 tbsp olive oil.
Mix to form a rough, shaggy dough and let rest for 30 minutes.
Start the first set of stretch and folds to develop gluten.
Perform 3-4 sets of stretch and folds every 30 minutes.
During the second set of stretch and folds, evenly incorporate the 2 tsp of salt, 8 oz of sliced olives, and 1 cup of grated Parmesan cheese into the dough.
Continue with remaining sets of stretch and folds.
Cover the dough with plastic wrap or a damp kitchen towel and let it rise at room temperature in a warm spot until doubled in size (about 4-12 hours depending on conditions).
Transfer the dough onto a lightly floured surface.
Shape it gently into a round or oval loaf.
Place the shaped dough, seam side up, on a piece of parchment paper in a medium bowl or banneton.
Let it proof for another 1-2 hours.
Preheat the oven to 450°F (230°C) with the Dutch oven inside for about 1 hour before baking.
While the oven is preheating, place dough in the refrigerator so it will be easier to score.
After the oven has preheated for an hour, remove dough from the refrigerator and place on a piece of parchment paper.
Score your dough and place in the dutch oven and cover with lid.
Bake for 30 minutes.
Remove the lid and bake for an additional 15-20 minutes until golden brown.
Remove the loaf from the Dutch oven and let it cool on a wire rack for at least an hour before slicing to allow the flavors to develop and the texture to set.