Preheat the oven to 230 ° C. Grease the drip pan (baking sheet) with baking spray or line it with parchment paper.
Mix the potatoes with 2 1/2 tablespoons of oil in a large bowl and season with salt and pepper.
Spread a layer of it on the baking sheet. Fry the potatoes for about 30-40 minutes until they are brown and cooked, turning occasionally. Then increase the temperature to 260 ° C. Grill the fries for about 5 minutes until they turn dark brown in places.
Mix the remaining 1/2 tablespoon oil, garlic and parsley in a large bowl. Add the hot fries, season with salt and pepper and mix well.