In a large bowl, whisk together the eggnog and cinnamon. The eggnog serves as a rich and creamy custard base, perfect for soaking the pumpkin brioche.

Slice the pumpkin brioche into thick pieces, about 1-1.5 inches thick if they are not already sliced. It is best to let them sit out to dry out a bit so they maintain their shape. Submerge each slice in the eggnog mixture, allowing it to soak for about 30 seconds on each side. You want the bread to absorb all that delicious eggnog, but not become too soggy.

Heat 1 tablespoon butter in a large skillet over medium heat. Once the butter is melted and sizzling, add the soaked pumpkin brioche slices to the skillet. Cook each slice for about 2-3 minutes on each side, until they are golden brown and crispy on the outside but still soft on the inside.

Transfer the pain perdu to a plate and top with a scoop of vanilla ice cream. Drizzle with caramel sauce for an extra layer of sweetness and indulgence.