In a large saucepan heat water until very hot (120-130°F). Stir butter into hot water until melted; add honey, dissolve. Allow to cool (110°F). Add sourdough starter and yeast, mix well. Add garlic powder, fresh oregano and cheeses.
In a mixing bowl blend together the rye flour, wheat flour and 2 cups of the unbleached white flour. Add the sourdough/yeast mixture to the flour mixture.
Turn out onto a lightly floured work surface and knead 8-10 minutes until very smooth, adding 1 cup of unbleached white flour at a time (as needed).
Place dough in a large, oiled bowl and turn to coat. Let rise until doubled. Punch down. Shape dough into loaf and place in a greased bread pan.
Allow to rise (about 45 minutes to 1 hour).
Preheat oven to 375°F and bake 45 minutes or until hollow sound when tapped on top.
