- Preheat the grill, setting the burners to high. Oil the grate.
- Individually wrap each potato in aluminum foil. Place on the grill, close the lid and cook for 30 to 40 minutes, or until tender. Let cool slightly.
- Meanwhile, grill the bacon slices for 2 to 3 minutes on each side, or until crisp. Drain on paper towels. Chop finely.
- Chop the whites of the green onions, then thinly slice the green part. Set aside separately.
- Lay the potatoes horizontally on a work surface and slice a thin layer off of each. Scoop out the potato flesh, leaving about 1/2 inch (1 cm) of flesh all around. Set the hollowed-out potatoes aside.
- In a bowl, lightly mash the potato flesh. Add the butter, sour cream, onion whites, 1 cup of cheese and half the bacon. Combine well. Season with salt and pepper.
- Generously stuff the hollowed potatoes. Sprinkle with the remaining cheese, bacon and onion greens.
- Reduce the grill heat to medium. Place the stuffed potatoes directly on the grate and continue cooking for 15 to 20 minutes, or until the cheese has melted.
For smaller portions, instead of simply cutting off the top of the potato (after the first baking), cut them in half to make eight servings rather than four.
For a spicy kick, add finely chopped pickled jalapeno pepper to the mashed potato stuffing.