you can do all these steps the day of just let the bread rest in the fridge for at least 30 minutes. you any bread you like any fruit dont like nuts leave them out.
tear what ever bread you have on hand in to one inch pieces into a bowl, cover with a paper towel leave out over night my loaf happen to be 18 oz which I think was to much I added an extra cup of milk to the egg milk mixture it did not look like it was enough for the 18 oz of bread
for the topping cream the one cup of brown sugar with the one stick of butter you can add another half cup of sugar if you like it sweeter, add pecans cover and chill over night. You see in this photo a cup or so of bread that I added to the topping mixture? I had a handful of old very sweet brioche bread I bought at wegmans I did not want to toss out so I thought considering I have reduced the sugar by half in most recipes this might be a good idea. Not necessary of course.
the next day, beat cream cheese, add zest, sugar beat another minute, add milk beat carefully add salt, vanilla beat, add one egg at a time beating in-between each. set aside you will want the bubbles that have formed to diminish as much as possible before adding to the bread.
I now buttered a 9x13 glass pan lightly then I sprinkled Turbinado, aka demerara sugar over the butter lightly. use any sugar you have. put a handful of bread covering bottom, sprinkle some pecans and blueberries I was able to do this three times at the end press bread down. pour the egg milk mixture over the entire surface.
cover and let sit for 30 minutes or over night I did the over night. take out of fridge let the chill come off cook at 350 deg. for 45 - 60 minutes depending on your oven you do not want to over cook it so after 35 minute test it with a knife you want it to come out clean.
I have seen some people top this dish with a sauce of 2 cups of confectioners sugar, 1 tsp of vanilla and 4-6 tsp of water or milk just enough to make a smooth sauce that you can drizzle. Or you can use a dollop of ice-cream or whipped topping.