Combine 500 grams einkorn flour, 350 grams water, and 100 grams active sourdough starter in a large mixing bowl and stir until a shaggy dough forms.

Cover the bowl and let the dough rest for 30 minutes at room temperature for autolyse.

Sprinkle 10 grams sea salt over the dough and gently pinch and fold for 3 to 5 minutes until fully incorporated.

Perform 4 coil folds at 30-minute intervals over 2 hours, then let the dough ferment undisturbed for an additional 2 hours or until it has increased by 50% in volume.

Turn the dough onto a lightly floured surface and pre-shape into a round, then rest uncovered for 20 minutes.

Shape the dough into a tight round by folding the edges toward the center, creating surface tension on top.

Place the shaped dough seam-side up in a floured proofing basket, cover, and refrigerate for 12 to 18 hours at 38°F to 42°F for cold proof.

Preheat a Dutch oven at 475°F for 45 minutes, then transfer the dough onto parchment paper and score the top with a sharp blade.

Bake the dough covered in the preheated Dutch oven at 475°F for 20 minutes.

Remove the lid and bake uncovered for an additional 15 to 20 minutes until the crust is deep golden brown, then cool the loaf on a wire rack for at least 1 hour before slicing.