Use a sheet of heavy duty aluminum foil (or two sheets of regular) to line a baking sheet. Make a ridge around the edges of the foil. Spread the foil with a teaspoon or two of olive oil (or butter if you prefer.)
Place the scrubbed and halved baby potatoes cut side down on the foil. Add some fresh rosemary if you'd like. Sprinkle with salt and pepper. Transfer the foil pack on the baking sheet to the grill. Slide the foil pack off the baking sheet and onto the preheated grill.
Cook over a hot grill (500°F.) until potatoes are almost fork tender. Resist the urge to turn them before they're crispy on the underside. Use tongs or a flipper to turn each potato piece so they'll get crispy on both sides.
When fork tender, sprinkle with blue cheese and close the lid of the grill. When the cheese has melted, remove the foil pack to the baking sheet to safely transfer it back to the kitchen. Sprinkle with cooked bacon bits, chives, rosemary, thyme or your favourite herbs. Serve right away.