To Make the Starter:

1. Combine sifted rye flour and warm water in a glass bowl or jar. Mix well until smooth. Cover with cling wrap. Using a sharp knife, make a few holes in it for air circulation. Store at room temperature (68-69°F) out of direct sunlight for 24 hours.
2. After 24 hours, feed the starter with another 1/2 cup of rye flour and 1/3 cup of warm water. Mix well and cover with cling wrap with few holes. Store at room temperature (68-69°F) out of direct sunlight for 24 hours. Repeat this step with feeding every day.
3. After 2-3 days you will see activity – bubbles and sour smell. The starter will grow and will double in volume. For best results, cultivate the starter up to five days.

To Make the Bread:

1. Dissolve the salt in warm water. Combine with starter and stir well. Then, add the sifted flour and mix with a wooden spoon until combined. Work until a smooth dough forms.
2. Put the dough onto a work surface and knead for 5 minutes. This dough is very sticky and you do not want to add more flour to it in the process. The best way to do this is to wet your hands. Use a dough scraper if the dough sticks to the surface.
3. Flatten the dough into a circle. Fold the outer edge into the center and press it down with the heel of your hand, turn the dough, and repeat the process several times. Place it in big bowl or round bread proofing basket with good layer of flour dusting. Cover with a damp tea towel.
4. Allow the dough to rise and to fermented at room temperature until it doubles in volume, approximately for 6 hours or overnight. If you want to speed up the process for a shorter rise time, place the dough in a warm place, such as a 120°F oven. But, for a long-term process, it is preferred to keep the dough at room temperature to prevent it from tasting too sour.
5. Preheat the oven, baking stone, and baking tray up to 430°F. Prepare 1 cup of boiling water.
6. Dust the hot baking stone with flour and place the dough. Score the top bread of using a very sharp knife. Remove excess flour from the baking stone to prevent the flour from burning.
7. Place the dough in the hot oven. At the same time, pour a cup of boiling water onto a baking tray, set it at the bottom of the oven, and immediately close the oven door. We need the steam to form a crispy delicious crust.
8. After 10 minutes, remove tray with water. Turn the oven down to 400°F. Bake for 45-50 minutes.
9. To check if the loaf is done, take the loaf out of the oven and turn it upside down. Give the bottom of the loaf a firm thump with your thumb, like striking a drum. The bread will sound hollow when it’s done. If you’re new to this technique, try doing this every 5 minutes toward the end of baking and you’ll hear how the sound changes.
10. Transfer to a wire rack to cool.