Heat the oven to 400 degrees. Rub the potatoes with olive oil and salt, then place them on a baking sheet. Bake for 45 minutes until the skins are crisp and the centers are soft.
Let the potatoes cool for 10 minutes. Cut each one in half lengthwise and scoop out most of the flesh into a mixing bowl, leaving a thin layer inside the skins.
Mash the scooped potato with the chopped spinach, sour cream, and half the cheddar cheese until the mixture turns light green and smooth.
Spoon the mashed filling back into the potato skins. Top each one with the remaining cheddar cheese and the crumbled bacon.
Return the filled skins to the oven for 10 minutes until the cheese melts and bubbles.
Remove from the oven and sprinkle with chives. Place two olive slices on each skin to form eyes before serving.