Spray a 9‑inch baking dish with baking spray with flour; set aside.

In a large bowl, combine the panettone cubes and the prepared eggnog. Toss to coat and let stand 20 minutes to soak.

While the bread soaks, melt the softened butter in a medium saucepan over medium heat. Whisk in the dark brown sugar and granulated sugar and cook, whisking occasionally, until the mixture is moistened and combined, about 2 minutes. Remove from heat and let cool 1 minute.

Whisk the eggs into the cooled sugar mixture one at a time until incorporated. Whisk in the ground nutmeg and ground cinnamon until smooth.

Pour the egg mixture over the soaked panettone and gently fold to combine. Fold in 1 cup (113 grams) of the sliced almonds.

Spoon the mixture into the prepared baking dish, smooth the top as needed, cover with plastic wrap, and refrigerate for 4 hours or up to overnight.

When ready to bake, preheat the oven to 350°F (180°C). Remove the plastic wrap and loosely cover the dish with foil.

Bake until the edges are slightly set, about 55 minutes to 1 hour.

Remove the foil and evenly sprinkle the cranberries and the remaining ¼ cup (28 grams) sliced almonds over the top.

Return to the oven and bake 20 to 25 minutes more, or until the almonds are lightly golden and an instant‑read thermometer inserted in the center reads 170°F (76°C).

Let the bread pudding cool 5 minutes, then serve warm.