1. Preheat oven to 425º. Place potatoes in a dish and prick all over with a fork. Microwave on high for 5 minutes. Transfer potatoes to a rimmed sheet pan lined with parchment paper. Brush potatoes with olive oil and season with salt. Bake until tender, 10 to 15 minutes.
2. Meanwhile, in a large skillet over medium-high heat, cook bacon until crisp. Transfer bacon to a plate and reserve fat.
3. When potatoes are cool, cut in half lengthwise. Using an ice cream scooper or spoon, remove middle, leaving a 1/4" thick shell. Add skins back to the sheet pan and brush with bacon fat all over top and bottom. Bake until golden and crisp, 4 to 5 minutes per side.
4. Reduce oven temperature to 375º. Sprinkle cheddar over potatoes and bake until cheese is melty. Top with bacon, a spoonful of sour cream, and green onions. Serve immediately.