Combine all ingredients in a standing mixer fitted with a dough hook and mix for 10 to 15 minutes.
Cover and let it ferment for 3 hours.
Knead the dough on a floured surface and form into a boule.
Coat a banneton (or a bowl lined with a cloth napkin) with flour and toss some pumpkin seeds and oats in the bottom. Put the boule bottom side up in this proofing basket, cover it with a towel, and let it sit for 60 to 90 minutes. Preheat your oven to 500˚F/260˚C with a Dutch oven inside.
When the dough has proofed, upend the dough into the Dutch oven and cover, turn the oven down to 350˚F/175˚C, and bake for 30 minutes. Remove the top of the Dutch oven to finish cooking, another 20 to 30 minutes.
Remove it from the Dutch oven and let it cool for at least an hour.