Mix together all purpose flour, whole wheat flour, salt, sugar and yeast. To this add the 1.5 cups of warm water. Stir well till incorporated using a wooden spoon or a spatula. Cover with a cling film and set aside for rising at a warm place undisturbed from 12-18 hours. It should be more than double in size. I typically leave it on the counter on a warm day and inside by oven with light on cold days.
After the first raise is done, pat it down to release all the air and add one cup muesli to it and knead for 2-3 minutes till the muesli is well mixed with the bread. Use well dusted hands to handle the dough, as the dough is pretty wet.
Shape the dough into a round shape and keep on a dusted parchment paper for 30 minutes. In the meanwhile, preheat a oven and the dutch oven (you can also use a standard cast iron pan with a cover) at 180C for 30 minutes.
At the end of 30 minutes, take out the dutch oven (be careful it will be hot) and place the shaped bread along with the parchment paper in the dutch oven. Close with a lid and bake for 45 minutes. Now remove the lid and bake for another 15 minutes.
Let it cool before slicing, serve warm with eggs, coffee and jam for the perfect Saturday leisurely breakfast!