Coat a large iron skillet with olive oil lightly and wipe with a paper towel to even out the oil. (You only want a very light coating of the olive oil.) Place the frozen roll in the pan. Cover with a light kitchen towel.
Place the pan with the frozen dinner rolls in a warm, dry place to rise for approximately 4 hours. (I usually heat my oven to 170℉. Once the oven is heated, turn off the oven and place the pan with the frozen rolls in the oven. Place a wooden spoon in the oven door to keep it cracked. The rolls will rise perfectly every time.)
Preheat the oven to 325℉. Once the rolls have risen, brush them with half of the melted butter and sprinkle with the chopped rosemary. Cook for 20 minutes until the rolls start to brown.
Once the rolls start to brown, remove from the oven and brush with the remainder of the butter and sprinkle with the salt flakes. Place the rolls back in the oven for 2-3 more minutes. Make sure to remove before the rolls get too brown.