In your stand mixer, add all of the ingredients. Mix on low speed until the dough has come together.
Cover with plastic wrap and let it rise for 8-10 hours until doubled.
Once the dough has doubled in size, remove the dough onto the work surface.
If you want to use these for dinner rolls, divide into 16 pieces. If you plan to use them for hamburgers, BBQ or another type of sandwich, I'd suggest dividing them into 10-12 pieces.
Shape each piece into a ball. Make sure that it has a smooth surface on the top. Place onto a baking sheet lined with parchment paper and press down on the dough ball slightly so that it is a bit flat. Place the dough balls about 2 inches apart to allow for rising space.
Repeat this process with the rest of the dough balls.
Cover them with plastic wrap to prevent them from drying out on top and forming a crusty layer.
Allow them to sit in a warm place for about 8 hours or more, until at least double in size, allow for it to rise to almost triple in size for an even lighter bun roll.
Once the potato flake sourdough bun rolls are about triple in size, preheat your oven to 350 degrees. adjust your rack to the second to lowest position in the oven.
Remove the plastic wrap and bake about 15 minutes for 16 dinner rolls, or about 18-20 minutes for 10-12 buns.
While they are baking melt your tablespoon or so of salted butter to baste on the tops. Baste them immediately when they come out of the oven!