In a dry skillet over medium heat, toast sesame seeds until golden and fragrant, 3-4 minutes. Stir frequently to prevent burning.

Transfer to a plate and let cool completely.

Mix toasted sesame seeds, poppy seeds, and everything bagel seasoning in a small bowl.

Separate into two equal portions. One for folding into the dough, one for coating the outside.

In a large bowl, add 375g room temperature water and 100g active starter. Mix with your hand until the starter is mostly dissolved.

Add 450g bread flour and 50g whole wheat flour.

Stir with your hand or a dough whisk until a shaggy dough forms with no dry spots.

Cover and let sit for 30-45 minutes.

Add 10g salt over the dough.

Use wet fingers to dimple the salt into the dough, then fold the dough over itself several times.

Pinch through the dough to distribute the salt evenly.

Cover and let rest 30 minutes.

With wet hands, grab one side of the dough, stretch it up, and fold it over the center. Rotate the bowl 90 degrees and repeat until you've gone around the entire dough. Cover and rest 30 minutes.

Perform another set of stretch and folds. After completing the folds, sprinkle half of your seed mix over the dough. Fold the dough over the seeds 2-3 times to distribute. Cover and rest 30 minutes.

If the dough still feels slack, perform one more set of folds. Cover and rest 30 minutes.

Let the dough continue to ferment at room temperature until increased by about 50%, with visible bubbles and a domed surface. This may take 2-3 more hours depending on your kitchen temperature.

Lightly flour your work surface and turn the dough out onto it.

Gently shape into a round and let rest 15-20 minutes.

Shape into a boule (round).

Lightly mist the shaped loaf with water or roll it on a damp towel, then press it into the remaining seed mix so the entire surface is coated.

Place the dough seam-side down in a floured banneton (so seeds end up on top when you flip it out for baking).

Cover the banneton with a damp towel or plastic wrap.

Place in the refrigerator for 6-8 hours or overnight.

Place your Dutch oven (with lid) in the oven and preheat to 475°F (245°C) for 30 minutes.

Turn the cold dough out of the banneton onto a piece of parchment paper.

Scoring|Score the top with a lame or sharp knife.

Carefully lift the parchment and dough into the hot Dutch oven.

Cover with the lid and bake for 20 minutes.

Remove the lid and bake for another 25-30 minutes until deep golden brown.

The internal temperature should reach 205-210°F (96-99°C).

Transfer to a wire rack and cool completely before slicing (at least 1 hour).

Turn dough out onto lightly floured surface.

Pre-shape into a round, rest 15-20 minutes.

Pull edges to center, flip seam-side up, cup hands around dough and rotate to build tension.

Coat with seed mix, place seam-side down in banneton.

After bench rest, flip the dough smooth-side down.

Fold the top third down and the bottom third up, like a letter.

Seal the seam with the heel of your hand.

Roll gently to taper the ends.

Mist, coat with seeds, place seam-side up in an oval banneton.

Preheat Dutch oven at 475°F for 30 minutes.

Turn dough onto parchment, score.

Load into hot Dutch oven, cover.

Bake covered 20 minutes.

Uncover, bake 25-30 minutes until deep golden.