Sprinkle yeast over warm water and let proof for 10 minutes. Stir in starter, honey, molasses, egg and butter. Beat in 2 cups flour, oats, salt and baking soda until well combined. Beat and knead in remaining flour until the dough is tacky but not sticky (it should be quite elastic but not get stuck to your finger when you press into it). Place in a greased bowl. Cover and place in an oven that has been preheated to the lowest setting (you can shut it off once it's preheated). This is to ensure that the dough warms up from the cold starter and that it rises beautifully. Let rise until double (approximately 1 hour).
Divide dough into 12-24 rolls depending on the size you want (12 for very large sandwich rolls, 18 for medium sized sandwich rolls and 24 for small dinner rolls). Place on greased or parchment lined baking pans. Cover with greased plastic wrap and let rise until double (about 1 hour).
Bake at 400F for 10-12 minutes or until golden brown. Transfer to cooling racks or paper towel to cool.
Makes: 12-24 rolls
* A trick that I do to make sure that my buns are cooked through is to flip them over and tap the bottom. If they sound hollow they're done!