1/2cupsoftened unsalted butter, vegan butter, or neutral oil
1cuppacked light brown sugar, divided
2tspground cinnamon, divided
1largechallah loaf
3largeeggs
1.5cupmilk
1tspvanilla extract
1/2tspkosher salt
Icing
1cupconfectioners' sugar
2tbspmilk
1/2tspvanilla extract
Instructions
Preheat the oven to 350°F (175°C/gas 4) and grease a 9 by 13-inch (23 by 33 cm) baking dish.
In a small bowl, stir together the butter, ½ cup (100 g) of the brown sugar, and 1 teaspoon of the cinnamon to make a thick paste.
Transfer the paste to the prepared baking dish and spread it into a thick even layer.
Using a serrated knife, cut the challah loaf into 2-inch (5cm) cubes. Arrange the cubed challah in the baking dish in an even layer.
In a large bowl, add the eggs, 1½ cups (360 ml) milk, 1 teaspoon vanilla the remaining ½ cup (100 g) brown sugar, the remaining 1 teaspoon cinnamon, and the salt; whisk until fully combined.
Add the egg mixture to the baking dish, distributing it evenly over the bread. Set aside until the bread fully absorbs the liquid, about 10 minutes.
Bake until the top is golden brown, 30 to 35 minutes. Let cool slightly, about 15 minutes.
While the bread pudding is cool, make the icing: In a small bowl, add the confectioners' sugar, 2 tablespoons milk, and 1/2 teaspoon vanilla and whisk until smooth and thick. Drizzle the icing over the bread pudding while it's still warm.