In a bowl add 1/2 cup starter (in winter you may need 2-3 tablespoon more starter), 1/4 cup whole wheat flour and little less than 1/4 cup filtered water. Mix well, cover and keep on kitchen counter for overnight or until it becomes double and bubbly. Next morning starter will be fully activated and ready to use.
Wash the spinach well. Chop roughly the blend into a smooth paste. You can add 1-2 spoon water if required.
In a large bowl mix whole wheat flour or atta, salt, spinach puree active sourdough starter and water. Mix well and knead a dough.
Add oil and knead well. You can use dough hook of your food processor to knead the dough. Smear the dough with oil. Cover and keep aside for 30 minutes.
Stretch and fold in every 30 minutes. After 4th stretch and fold let the dough rest for 3-4 hours or until dough becomes double. When dough rise well keep the covered bowl in refrigerator overnight.
Next morning sprinkle little flour on kitchen counter or silicon mat. Take out the dough from bowl. Grab the dough from top and gently roll a few times. Push and pull gently. Cover the dough for 30 minutes again.
Grease a loaf pan. After 30 minutes give the dough final shape and transfer to the greased loaf pan. Press gently with your wet fingers. Watch video recipe for details.
Cover and let it proof for 2-3 hours or until it becomes double.
Preheat the microwave convection or hot blast mode at 200°. Bake in covered loaf pan at 190° for 15 minutes. Place a bowl of hot water under or beside the pan.
After 15 minutes take out the bowl of water. And remove the cover of the pan. Bake again at 180° for 15 minutes or until the crust becomes golden brown.
After 10 minutes take out the bread on a cooling rack. Let the bread cool down completely before slicing. Your soft and delicious bread is ready to serve.