Stir in the yeast and sugar and let sit for 5 minutes until foamy.
Stir in the flour.
Cover loosely and place in a warm place 8-12 hours.
For the bread
Add the warmed milk to a large bowl. Stir in the starter.
Stir in the sugar, salt and baking soda until the dry ingredients are dissolved.
Add the flour 1/2 cup at a time, stirring to combine until smooth. The dough will end up sticky and thick.
Spray two 8" (or three 6") pie pans with non-stick spray.
Sprinkle the bottoms of the pans with the corn meal.
Divide the dough between the pans. Just plop into the centers of the pans. Don't worry about it being pretty, it'll spread out as it rises.
Lightly spray the tops of the dough with non-stick spray.
Loosely cover the pans and let rise for 1 hour in a warm spot. I recommend covering the dough with something that won't stick to it, such as upside down pie pans.
After the dough has risen, preheat your oven to 375 F.
Spray the tops of the dough again with non-stick spray and bake for 20 minutes until golden brown. Remove to racks to cool.
For the creamy garlic dressing
Whisk together all ingredients. Store in a squirt bottle for easy dispensing.
For the sandwich
Cut the bread in half, horizontally.
Squirt the bread with the garlic dressing and yellow mustard.
Add the remaining sandwich ingredients.
Slice into quarters and serve.
Note: I like to have my cheese melted a bit, so I wrap the assembled sandwiches in foil and insert them into a preheated 350 F oven for 5-10 minutes.