Scald the milk in a small pan. Remove from heat and add butter, real salt, and warm water. Let cool until lukewarm before proceeding.
Put starter sponge in large mixing bowl and add the lukewarm milk mixture to the stater bowl.
Stir in enough flour to make a medium stiff dough. This should be 4-5 cups depending on your humidity and temperature. I prefer to use a wooden spoon, but if you prefer your mixer, use it.
Turn the dough out onto a floured surface and use the remaining flour to knead your dough for 10 minutes. You dough will be soft, pliable and still a little sticky when done
Don’t cut the time, (if you are using most flours) this is important to activate the gluten to give your bread a nice rise and texture. If using Einkorn flour knead only 5 mins - see note below My best tip for kneading and handling wet, tacky dough is to moisten your hands with water instead of dusting them with flour. Re-wet them every time the dough begins to stick to you. This avoids the mess of flour dust getting everywhere and keeps the bread moist as well. If you use a mixer to knead your dough it should only take 2-3 minutes.
Oil a large bowl, I grease the large bowl that I mixed the dough in.
Cover with a damp kitchen towel and let rise in a warm place until doubled.Sourdough bread takes much longer to rise than bread made with active dry yeast. It may take 3-6 hours for this to happen, it just depends on the humidity and temperature.More humidity makes shorter rising times because it allows for more expansion since the air is lighter than dry air (seems backwards I know) and cooler temps take longer for bread rise to finish. Lightly oil two 9”x5” bread pans.
Place them in two lightly oiled bread pans.
When the dough has doubled in size, separate it into 2 equal portions and shape into loaves. Place them in your prepared bread pans.
(optional) You can brush the top of the dough with olive oil or egg wash for a shiny crusty top. You can also sprinkle flax seeds or seed toppings on top of the loaf, if desired. If you do add these, gently, slightly press them into the top of the loaf.
Cover with a towel or dish cloth and set in a warm spot to rise. I put mine on the stove top and turn the oven on to preheat. This second rise should take 45 mins to one hour.
Preheat your oven to 400 degrees F.
(optional) 10 mins before you put the bread in the oven, put a pot of boiling water on the oven rack and remove it when you put your pans in. I do this to increase the humidity in the oven to create a little more rise.
Bake for 40 mins – 1 hour depending on your pan size, how your oven cooks, the color of loaf you want and your elevation.
Take pans out of the oven and let cool in pans for 5 minutes then remove loaves from pans to a wire rack to finish cooling. For a soft, buttery top, brush the tops with butter.
When you remove the loaves from the pan, tap the bottom of each loaf. a dull, hollow sound means the loaf is done.
Let the loaves cool for at least one hour before you cut them using a sharp knife.