In a large pot, cover diced potatoes in cool water covered over HIGH heat. Continue with hamburger gravy instructions. When water begins to boil, remove lid. Boil 10-15 minutes until potatoes are very tender. Reserve ½ cup cooking water, drain the rest. Add reserved potato water, butter, salt, and black pepper. Mash with a potato masher and stir to combine. Start with 2 tablespoon of reserved water and add to the consistency you prefer. Start with 4 tablespoon of butter and add to your liking.*****
In a large deep skillet add neutral oil and turn burner to MEDIUM. When skillet is warm add ground beef breaking up with wooden spoon. Season with 2 pinches of salt and 3 dashes of black pepper.
Brown ground beef until no pink remains about 3-5 minutes. Remove with a slotted spoon to a bowl to catch drippings.
Add onion and 2 pinches of salt to hot pan containing rendered meat fat. Sauté stirring often until onion is very browned almost burnt looking around the edges 8-10 minutes.
Add Homemade Beef Bouillon Powder and salt. Cook stirring constantly until fragrant, about 30 seconds. If pan looks dry add additional oil ½ tablespoon at a time.
Add ground beef and accumulated juices back into the pan and stir to combine.
Add 1½ cups water to the pan and stir to combine.
In a small cup or bowl add ¼ cup water and arrowroot starch. Use a fork to mix until starch is completely absorbed and no lumps remain. Add to pan, stir to combine.
Turn heat to MED-HIGH and bring to a boil. Reduce to MED-LOW and simmer until gravy is thickened and reduced down by ¼ or to your liking.