Wash the rosemary, dab dry and pluck the needles from the twigs. Peel garlic and chop finely. Brush the potatoes thoroughly with a vegetable brush, wash and cut into slices of about 1/2 cm thickness. Clean and wash the pepperoni. Heat olive oil in a pan and fry potato slices in it at medium heat while turning for 7-8 minutes.
Add rosemary, pepperoni, garlic and olives about 2 minutes before the end of the frying time. In the meantime, cut the cheese into cubes. Season potatoes with salt. Serve the potatoes sprinkled with feta cheese on two plates. Garnish with rosemary as desired