Makes two loaves. Combine in a large bowl the oats, whole wheat flour, brown sugar, salt, and butter. Pour boiling water over mixture. Stir to combine. When batter is cooled to lukewarm, add the starter and stir in the flour. When dough is stiff enough to handle, turn onto floured board and knead for 5 to 10 minutes. Place in a greased bowl, cover and let rise until doubled (about 4 hours in my oven with the light on). Punch down and separate into 2 equal balls. Shape into loaves and place in greased 9 X 5 X 3 inch pans. Let rise until doubled again. Bake for 30 to 40 minutes at 350 F. Cool on rack, brushing loaves with butter or margarine for a soft crust.
Ruth is a friend of mine at church and she shared the recipe with me several years ago. I just modified it a little to use the sourdough starter which makes it better than ever. I take the sourdough starter out of the refrigerator the night before and feed it to make it good and active. The resulting bread is fantastic. Please share the recipe with your friends if you like the bread.
Tester's Notes: This recipe makes beautiful soft dough that bakes into great pan bread or it can be made into very tasty dinner rolls. Take the words "punch down" with a grain of salt. Be gentle with this dough. The more air you work out of the dough when forming the loaves, the longer it will take to recover volume in the second rise.
Be sure to allow enough time for the batter to cool to lukewarm before adding the sourdough starter. It took two hours or more when tested. Taste testers disagreed on the amount of salt, some preferred a little less; others liked the taste with the full tablespoon.
Ovens vary. Test bakes took around 50 minutes in the test kitchen. We removed the bread from the pans for the last ten minutes of baking to brown the bottom half of the loaves.
Treat yourself to real butter in the dough. This bread is worth it. Also butter the pans, you will be rewarded with an amazing butterscotch smell when the butter toasts the brown sugar sweetened dough while baking.