Step 1

Toast the Bread - Set the oven rack to the center position and heat to 300ºF (149ºC). Cut the bread into 1-inch cubes, about 9 to 10 cups. Spread on a large sheet pan. Bake for 20 to 25 minutes, stirring halfway through. The bread should be lightly golden and dry on the surface. Cool on the tray for 10 minutes. It will become crisper.

Step 2

Prepare the Casserole Dish - Grease a 3-quart or 9x13 baking dish with the softened butter. Add the dried bread in an even layer. Set aside. Increase the oven temperature to 350ºF (177ºC).

Step 3

Warm the Milk and Sugar - In a large heavy-bottomed saucepan, bring milk, cream, and granulated sugar to a low simmer over medium heat. Stir to dissolve the sugar and cook for about 5 minutes. Do not heat over 120ºF (49ºC); the milk should be warm. Turn off the heat and stir in vanilla. Remove the pan from heat and set aside.

Step 4

Temper the Custard - In a medium bowl, whisk the eggs, yolks, and salt. Very slowly, pour a ½ cup of the warm cream mixture into the eggs, whisking continuously. Add in another ½ cup, whisking between each addition until a total of 2 cups have been added. This is the tempered egg mixture.

Step 5

Flavor the Custard - Pour the tempered eggs back into the saucepan and whisk to incorporate thoroughly. Whisk in the cinnamon, nutmeg, and raisins (if using).

Step 6

Soak the Bread - Pour the custard mixture over the bread, stirring a few times to soak. Allow the bread to sit and absorb most of the liquid for 30 minutes. Push any exposed bread down into the custard with a spoon.

Step 7

Bake - Place the baking dish in a large roasting pan. Slowly pour enough hot water into the pan to go about halfway up the sides of the baking dish. Carefully transfer to the oven. Bake until the pudding appears set in the center and the temperature reaches 170 to 175ºF (77 to 80ºC) on an instant-read thermometer, about 60 to 75 minutes.

Step 8

Cool - Carefully remove the roasting pan from the oven and then remove the baking dish from the roasting pan. Allow to cool for 60 minutes before serving, so it’s easier to cut.

Step 9

Make the Bourbon Sauce - In a small saucepan, melt the butter over low heat, stirring occasionally; do not let it simmer. Whisk in the brown sugar, ensuring the mixture does not exceed 135ºF (57ºC). Add the egg and quickly whisk to combine. Continuously stir and cook until it thickens enough to coat a spoon and reaches 155 to 160ºF (68 to 71ºC), about 3 to 4 minutes. Turn off the heat. Stir in the bourbon, vanilla, and salt. Taste and add more bourbon if desired, 1 teaspoon at a time. Strain the sauce if needed to remove lumps. It will thicken more as it cools.

Step 10

To Serve - Dust the bread pudding with powdered sugar and drizzle with warm bourbon sauce.