Prep: Preheat the oven to 450°F (230°C). Line a baking sheet with parchment paper.
Shape the Potatoes: Peel the potatoes and trim each into a rectangular block. Reserve the trimmings for another use.
5 large russet potatoes
Slice: Slice each block 1/16 inch (1.5 mm) thick on a mandoline, keeping the slices from each potato together in a stack. Pat each stack dry with paper towels.
Skewer: Divide each stack in half and thread each half onto a cocktail pick, keeping the slices aligned, for a total of 10. Trim the sides of each stack into an even square, if desired.
Season: Arrange the skewers on the prepared baking sheet. Brush all sides with clarified butter, reserving a small amount, and sprinkle with seasoned salt.
1/4 cup clarified butter, 1 pinch seasoned salt
Bake: Bake for 15 minutes. Reduce the heat to 425°F (220°C) and bake 25 to 35 minutes more, flipping halfway through and brushing with the reserved butter, until the edges are golden and the centers are tender.
Finish: Transfer the crème fraîche to a piping bag. Pipe crème fraîche over each skewer, then top with chives and caviar. Serve.