Whisk together the remaining ingredients in a large bowl, using both the zest and the juice of one orange. Add the bread and toss to coat.
Coat a 9 by 13 inch baking dish with cooking spray. Pour the bread pudding mixture into the dish. Cover and let sit at room temperature for 20 minutes.
Preheat oven to 325F.
Bake the pudding on the lower middle rack until it is golden brown and puffing up around the edges, with a slight jiggle in the middle, approximately 45-50 minutes.
Let cool for 30-45 minutes before serving warm. This pudding is great served with whipped cream or ice cream.
If using a very light and airy bread like French or Italian bread, it is best to dry it out before using as it will hold its shape and volume better. Either cut and leave out, uncovered, overnight or dry out in a warm or low oven.You can let the bread soak in the refrigerator for up to 24 hours if needed.The lemon is noticeable but not overpowering in this recipe. For a subtle lemon, or straightforward blueberry bread pudding, reduce lemon zest to 1 Tablespoon and lemon juice to 2 Tablespoons.Easily halve the recipe for a smaller crowd! Just cut everything in half and skip the extra egg yolk completely.