In a medium-sized bowl, gently whisk together the yeast, warm water, and sugar. Let it stand for 5 minutes until bubbly.
Whisk in the warm milk, baking soda, salt, and 1 cup of the flour until smooth. Then mix in the remaining flour.
Spray two 9-inch cake pans (or pie pans) with nonstick cooking spray and dust the bottoms with cornmeal. Divide the dough between the pans and spread it out a little. The yeast will do the rest. Spray plastic wrap with nonstick cooking spray and lightly cover each pan. Proof (let rise) in a 150-175 degree oven (or a warm, draft-free place) for 1 hour.
Preheat the oven to 375 degrees F. Remove the plastic wrap and bake for 20 minutes, or until golden brown. Brush the tops of bread lightly with melted butter and cool in pans completely.
Dust off the loose cornmeal. Slice the bread loaves in half horizontally, and start creating your sandwich masterpiece!
NOTES: To make copycat Schlotzsky's original sandwiches, layer on creamy garlic dressing (or Caesar dressing), cheddar cheese, Parmesan cheese, ham, salami, mustard, and sliced black olives. Toast in the oven until the cheese melts, then add lettuce, tomatoes and onions.