Preheat the oven to 325 degrees F. The bread will need to be dry so it can absorb the sauce later and not completely fall apart. Either leave the bread out over night, or put it in the oven on a cookie sheet for about 5 minutes at the 325 degrees F.
Break up the bread. Paula Deen says to cut up the bread in cubes. Cutting up the bread might keep you from smashing it with your fingers. I just ripped the bread apart with my fingers.
Grease the dish, then place the bread in it. To grease a dish really well my mom would put a napkin in margarine and then wipe it around the pan. It creates a thicker layer than a spray, and I think it is healthier than butter.
In a bowl, mix the sugars and cocoa powder. Add milk and whisk to combine.
In another bowl, add vanilla extract, almond extract, cinnamon, and optional spices to beaten eggs. Pour egg mixture into the milk mixture and mix well. Break up the chocolate bars into small pieces however you see fit. I would suggest to a size smaller than the little rectangles
of the chocolate bars.
Pour the mix over the bread. Let it stand for 20 minutes while stirring occasionally. Once it has stood for 20 minutes insert the marshmallows in with all of the bread. Then slide graham crackers in along the sides of the dish. I put it in earlier and they started falling apart and falling in with everything else when I stirred it occasionally. Waiting till the last second should prevent this.
Place it in the oven and let it cook for 1 hour or until set. If you want't, at this point you could take the pan out, turn the oven to broil, and place marshmallows on top. Put it back in the oven for 30 seconds or less to toast the marshmallows. A knife should be able to inserted and removed clean - except if inserted into a marshmallow, obviously. It can be served warm or cold, but who eats cold s'mores. Serve on graham crackers if you want and enjoy!