The day before, set the bread out to go stale, if desired. I prefer chewier bread and leave it as fresh.
Preheat the oven at 350-degrees (if you're baking this promptly). Grease an 8x8 casserole dish. Cut the 12 ounces of bread into chunks. Melt the butter.
In a medium bowl, combine the milk, eggs, butter, brown sugar, cinnamon, nutmeg, pumpkin puree (if using) and vanilla. Whisk until all ingredients are combined.
Spread the bread evenly within the dish. Pour the milk mixture over it. Press the bread in lightly to make sure nothing is dry. (If you're making this ahead of time, cover with foil and set in fridge for several hours.)
Bake for 45-55 minutes, until the knife inserted in the center comes out clean.
!Serve hot, at room temperature, or straight from the fridge! Top with maple or agave syrup, nuts, whipped cream, caramel sauce, or fruit or nut butter. Anything is good. Plus, leftovers can be chopped into serving-size squares and frozen.
!OM NOM NOM!