Step 1

Make the Levain:In a clean jar, mix the sourdough starter, bread flour, and water for the levain.Cover and set in a warm location (between 75-80ºF) for about five hours until doubled and bubbly.Alternatively, skip making a levain and use 90 grams of active sourdough starter below.

Step 2

Autolyse:When the levain is ready, mix together the bread flour, whole wheat flour, and water in a mixing bowl.Make a well in the center of the flour and pour in 307 grams of warm water.Use a dough whisk or your hands to mix together the flour and water just until it comes together.Cover and rest in a warm location for 30 minutes.

Step 3

Add Levain, Salt, and Mix:Add all of the levain into the bowl and dimple it into the dough. Then, stretch and fold the dough for a few minutes to incorporate.Cover and rest in a warm location for 30 minutes.Sprinkle the salt on top. Dimple the salt into the dough. Stretch and fold the dough for about 5 minutes until thoroughly mixed and the salt dissolves. While mixing, if the dough seems stiff and you think the dough can handle it, you can add another 10 grams of water.Cover and rest in a warm location for 30 minutes.

Step 4

Bulk Fermentation, Lamination, & Folds:At 78ºF (26ºC), bulk fermentation typically takes about 5 hours.After 30 minutes, perform one set of stretch & folds. Rest 30 minutes.Dampen a large work surface and your hands and stretch the dough out thinly into a large sheet. Sprinkle the chopped sun-dried tomatoes, capers, oregano, and red pepper flakes all over the surface. Fold the dough into a packet to laminate it (more instructions on how to laminate the dough in the post above). Rest 45 minutes.Separated by 45 minutes or so, perform 2-3 more sets of stretch and folds on the dough during bulk fermentation. Rest for the remainder of time.At the end of bulk fermentation, the dough should be smooth, feel full of air, have visible bubbles, and jiggle if shaken. The dough should almost double.

Step 5

Shape:Lightly flour the top of the dough and the counter. Gently loosen the dough from the sides of the mixing bowl and turn the dough out onto the counter.With the help of a bench scraper, shape the dough into a batard (oval) or boule (round). If there are any inclusions on the surface, try to stick them back into the dough so they don't burn during baking.Lift it up and place it into a floured banneton.Stitch the dough in the banneton if it's still slack.Cover and rest for 15-30 minutes.

Step 6

Cold Overnight Proof:Place the covered banneton into a refrigerator to proof overnight and for up to two days.

Step 7

Bake:Place the empty Dutch oven with lid in the oven and preheat for an hour at 500°F (260ºC).Once preheated, remove the banneton from the refrigerator and turn the dough out onto a piece of parchment paper. Score the dough with a sharp bread lame about ¼-½" deep.Transfer the scored dough to the Dutch oven and cover it with the lid.Bake at 500°F (260ºC) for 20 minutes. Remove the lid, lower the oven temperature to 450ºF (232ºC) and bake for about 15 minutes with the lid off.Remove from the oven and cool on a wire rack for at least an hour before slicing.Slice and enjoy with cheese or a drizzle of good olive oil.