1. In a large pot pour water with salt and cook the potatoes until fork tender.
2. Once done drain and pat dry the potatoes cubes.
3. Preheat the oil in a frying pan upto 250 degree.
4. Once the oil is hot fry the potatoes for 5 minutes or until golden brown on all sides.
5. Once done drain the excess oil on paper towel.
6. Place it on a sheet pan and place it in the freezer for some time.
7. Again preheat the same oil upto 375 degrees.
8. Fry the potatoes again until golden brown.
9. Towards the end add the rosemary springs and fry them along with the potatoes.
10. Remove and drain the excess oil on paper towel, season with kosher salt.