Boil potatoes until knife pierces through easily, about 10-15 min. Let cool, roughly crush potatoes with your palm and the skin will easily comes off. Include or discard skin as desired.

In a large non-stick pan, crisp pancetta on low heat until fat renders and pancetta is crisp but not burnt. Remove pancetta from pan, set aside. Leave rendered fat behind.

Keep pancetta fat on low heat. Carefully add crushed potatoes and spread out in an even layer. Still on low heat, sprinkle about a cup of grated Gruyère on top, cover and let everything steam for about 5 minutes.

Use a wooden spoon to further break up the potatoes and gently stir in the melted cheese. Crumble up your reserved cooked pancetta. Add half of the pancetta crumbles, another ½ cup of grated Gruyère and stir everything to combine. Spread pancake out evenly and flatten with a spatula. Turn heat up to medium-high and cook until the bottom of potatoes is golden, about 5 min. Press down and check occasionally.

Carefully flip pancake by putting a large serving plate over the pan and turning it over so the bottom is facing up. Things will be hot so use a dish towel if needed. Slide the pancake back into the pan, golden side facing up. Cook for about 3 more min, pressing down once in a while. When ready, slide pancake onto the serving plate.

Cut into wedges and serve with parsley, crème fraîche and remaining pancetta crumbles. Be careful about adding salt because the Gruyère and pancetta already provide a good amount of seasoning and flavor.