Dough: : Mix all the ingredients for the Levain in a small bowl. Cover with wax wrap and let sit overnight. * Add levain in a large mixing bowl and add water. Quickly mix the water with the levain. Add flour and knead for one minute on low. Cover with wax wrap for 30 minutes. After 30 minutes mix salt and the remaining water and add to the dough. Knead on low for 5 minutes. Cover with wax wrap.
Folding: : After 30 minutes fold the dough with a dough scraper form each side to its opposite. Cover for another 30 minutes, fold again. Repeat this process 5 times in total. Meanwhil flour proofing basket (if you like, place a towel in the proofing basket and flour the towel. )
Shaping and Proofing: Place the dough on a floured surface. Flatten slightly and fold opposite ends into the middle. Tuck together and turn upside down so it can rest seam-side-down for 5 minutes. Place shaped loaf seam-side-up in the proofing basket. Cover with a dish towel and let proof overnight in the fridge or 2-3 hours at room temperature.
Baking: Place Dutch oven in the oven and preheat at 280°C. When the oven is hot turn temperature down to 250°C. Remove Dutch oven from oven and place your risen loaf directly from the proofing basket into the Dutch oven. Cover with the lid. Bake for 20 minutes. After 20 minutes remove lid and bake for another 25. Let the bread cool on a cooling rack and enjoy! Sourdough stays fresh for about a week. *to check if the Levain is ripe, add a teaspoon into water, if it floats it is ready.
Recipe by at https://fannythefoodie.com/2020/03/31/rye-sourdough-bread-recipe-sourdough-faq/