In a large mixing bowl, whisk together warm water and yeast. Let sit for 10 minutes until bubbly. I wasn’t persnickety about the temperature of the water. It’s not that serious. Just make sure it is warm, not hot, to the touch.

To the large bowl with the yeast, add rye flour, whole wheat flour, all-purpose flour, and salt. Stir to combine with a large rubber spatula or wooden spoon. Scrape down the sides of the bowl.

Cover with plastic wrap or a tea towel and allow to proof in a warm spot for 1 hour.

Perform 1 set of folds. Using a bowl scraper to help, scoop up one side of the bread and fold over the center. Rotate 90° and repeat the folding until you have folded all the sides. Cover and continue to let the dough rise in a warm spot for an additional hour.

Prepare two 12-inch squares of parchment paper. Excess parchment paper won’t improve the crust. Dust the top of the dough (in the bowl) generously with flour and lightly flour a smooth work surface such as a countertop. Using a bowl scraper, turn the dough out onto the floured surface and divide it into two equal pieces.

Working with one piece of dough at a time, fold each of the four corners into the center and then flip the dough packet over. Use both hands to pull and tighten the dough into a circle by pulling towards you quickly, then rotating 90° and repeating. Flouring your hands as needed.

Once shaped, place each piece in the center of a piece of parchment. Cover and final proof 40 minutes.

Preheat the oven to 425°F convection (with the fan) if you have that option. Preheat the oven to 450°F conventional (no fan) if you do not. If you are using a Dutch oven to bake, preheat the top and bottom of the Dutch oven along with the oven.

When you are ready to bake, if proofing in bowls, lift the dough out using the parchment paper. Score using a bread lame or razor blade. I prefer to try to make a square on the top of the dough to encourage rising up but this is particularly difficult with this dough. Do not be discouraged.

Working carefully and efficiently, remove the Dutch oven or baking sheet from the oven and close the oven door. Open the top of the pot and place the dough inside using the parchment paper. Replace the top and place it back in the oven.

Bake for 20 minutes and either remove the top of the Dutch oven or any remaining water (probably none), but opening the door will release any trapped steam and allow the crust to form.

Reduce the oven temperature to 375°F convection (if using a fan) or 400°F conventional (if not). Continue baking an additional 15-20 minutes until the outside of the loaf has browned.

Remove bread from Dutch oven or baking sheet and cool on a wire cooling rack.