Scrub and rinse potatoes then dry. Lay each potato on a square of aluminum foil (large enough to fully cover), drizzle 1 tsp olive oil over each potato and rub around potato to evenly coat.
Sprinkle with sea salt and pepper (I used a slightly heaping 1/8 tsp salt and about 1/16 tsp pepper per each). Wrap foil around each potato.
Pour 1/2 cup water into a 6 or 7 quart slow cooker then transfer potatoes to slow cooker.
Cover with lid and cook on high heat 4 - 5 hours or low heat 7 - 9 hours, until potatoes are tender (smaller potatoes will cook faster than the larger). Serve warm with desired toppings.
Notes
Method adapted from Cook's Illustrated (they used vegetable oil cooking spray in place of olive oil which would also work fine).Topping Ideas