Wash the potatoes and pat them dry. Using a fork, pork holes in each side of the potato.
Lightly brush each potato with olive oil and sprinkle with sea salt.
Place the potatoes in the slow cooker, cover, and cook on high for 4 1/2 to five hours or on low for 7 1/2 to 8 hours.
Potatoes are done when you can easily pierce them with a fork.