Cube 4 cups of challah or brioche bread into roughly 1-inch pieces. Spread them out on a baking sheet and allow to dry slightly for about 30 minutes if fresh.
In a large bowl, whisk together 2 cups of milk, 1 cup heavy cream, 3/4 cup sugar, 4 large eggs, 1 teaspoon vanilla extract, 1 teaspoon ground cinnamon, and 1/4 teaspoon salt until smooth and well combined.
Place bread cubes in a greased 9x13-inch baking dish. Sprinkle 1 cup dried cranberries and 1 cup white chocolate chips evenly over the bread. Pour custard evenly over the top, pressing down gently with a spatula.
Allow the pudding to sit for at least 20 minutes at room temperature to let the bread absorb the custard fully.
Preheat oven to 350°F (175°C). Cover the baking dish with aluminum foil and bake for 35 minutes. Remove foil and bake an additional 15-20 minutes until top is golden and a toothpick inserted in the center comes out clean.
Let the pudding cool slightly before serving. Optionally, serve with a drizzle of cream or a dusting of powdered sugar.
