For frittata
- Preheat oven to 200°C (400 °F).
- Bring a large pan of salted water to a boil. Cut the potatoes into very thin slices using a mandolin. Plunge into boiling water to blanch for 3 minutes. Drain carefully to keep slices intact; blot dry and reserve.
- Heat olive oil in a skillet over medium heat. Add pancetta and fry until crisp and golden.
- Add French shallots to skillet and sweat for about 5 minutes (reduce heat if necessary).
- Add minced mushrooms and oregano, and sauté over medium-low heat until mushrooms are cooked and have reduced in volume, about 10 minutes. Reserve.
- In a large bowl, beat eggs with 15% cream. Add sea salt and a little freshly ground black pepper.
- Generously oil the bottom and sides of a cast-iron skillet or deep pie dish. Arrange some potato slices in a layer in dish or skillet to cover bottom completely, overlapping slightly. Spread one quarter of mushroom and pancetta mixture on top, and then pour in one quarter of egg mixture. Repeat these layers, ending with a layer of potatoes. Press down to compact ingredients and moisten all the layers. Using a pastry brush, oil top layer of potatoes, and season with salt and pepper.
- Bake for 30 minutes, until potatoes are golden and soft, and eggs are cooked. Cool for 10 minutes before cutting into slices.
For topping
- In a bowl, crumble goat cheese with a fork.
- Add cream and black pepper (to taste) and then mix with an electric beater until cheese is light and smooth.
- Serve whipped cheese by the spoonful on each frittata serving.
Chef’s secret
The goat cheese topping can be prepared ahead of time and stored in an airtight container in the fridge.