Day one:
2 cups unbleached all purpose flour
2 cups water
1 tablespoon dry yeast
1 tablespoon sugar

Use large bowl - stir together with wire whisk, cover with towel and let sit 24 hours.

Day 2 :
Stir the mixture again and let sit another 24 hours.

Day 3
Mix 4 cups white rye flour (I buy this on E-Bay in 50 lb bags)
2 cups all purpose unbleached flour
1/4 cup dry instant mashed potatoes
1/2 teaspoon sugar
1 tablespoon salt
all of the above sour dough
5 1/2 ounces warm water

I mix this in a large mixer with dough hook about 7 minutes.

place in bowl sprayed with a non-stick spray, cover with towel and let sit 1 hour.

After 1 hour mix again with dough hook for 3 minutes.

Dough will be heavy and a little sticky - may need a spatula to get it out of the mixer.

Shape into 1 large bread or 2 small breads and let rise on a cookie sheet for 1 hour. (at about 1/2 hour turn oven on to 425 degrees) ((prepare cookie sheet with parchment or corn meal))

Bake for 45 minutes in middle rack of oven (I turn mine about 1/2 way so it bakes evenly)

Brush with butter as soon as it comes out of oven. Let cool before cutting. This bread freezes well.