Preheat oven to 325 degrees.
Take the 'ulu and place in a roasting pan along with 3 cups of water and cover tightly with foil.
Place in the oven and allow to steam for 1-1.5 hours until fully cooked. Remove 'ulu from pan and cool in the refrigerator for 2 hours minimum, until fully cooled. (This can be done ahead of time.)
Remove cooked 'ulu from the refrigerator, and peel outside skin. Using a mandolin, French fry cutter, or knife, cut into desired shapes, making sure to remove all seeds. Lay all fries out ready to be fried.
Heat frying oil in a large pot (or heat deep fryer) to 365 degrees, making sure there are at least 6 inches of oil in the pot. In small batches, add 'ulu fries to oil and cook each until golden brown, and remove from hot oil with skimmer onto a paper towel-lined sheet tray. While fries are still hot from the fryer, sprinkle kosher salt over them to taste. Make sure not to overcrowd the frying pot, or stack fried 'ulu fries too high after cooking (they’ll steam themselves and lose crispiness).
Serve immediately.