Preheat oven to 350°F degrees. Place Square Savarin Tray (or Straight Muffin Tray) on Medium Perforated Baking Sheet and set aside.
Stir together the sugar and nutmeg in Stainless Mixing Bowl. Add the beaten eggs, milk, and vanilla. Whisk to combine into a custard. Add bread cubes along with raisins and nuts (if using them), and stir to mix everything well.
Set the pudding mixture aside for 20-30 minutes to allow the bread to absorb the custard.
While the pudding is resting, make the sauce by combining the water, brown sugar, and nutmeg in a small saucepan.
In a small bowl, stir together the bourbon (or ¼ cup water, if not using bourbon) and cornstarch, mixing them well.