My Nonna Franca made these potatoes for me when I visited Rome with her right after I graduated from H.S. I was young and I'd never had such a good potato ( my American mother wasn't really a cook). I remember I came back to the U.S. and tried to recreate the recipe, at first using the wrong kind of potato. Eventually I learned the right potatoes to use and just how long to fry them for. Yet, still, mine are good, but I've never been able to make them as good as Nonna did. It's funny how an Italian grandmother can simply fry a potato better! —Jenifer Mangione
Heat the oil in a large skillet on medium heat for approximately 20 minutes. You want the oil to be hot enough that the potatoes sizzle when you add them.
While the oil is heating slice the potatoes. First slice them in half, then slice the halves into 1/4 inch slices and then cut those in half.
Place the potatoes and the 3 sprigs of fresh Rosemary in the pot and cover for 7 minutes. Uncover and cook for 15 minutes. Then turn the potatoes and cook for an additional 15 minutes. You want them to be lightly browned.
Remove the potatoes from the oil using a slotted spoon and then lay them on a plate lined with paper towels to remove excess oil. Let them sit for five minutes. Add sea salt, toss and serve!