Bring a pot of salted water to a boil for the potatoes. Peel and cut the potatoes into pieces. Cut the pork tenderloin in half lengthwise and set aside.

Cook the potatoes until tender in the boiling water. While the potatoes are cooking, mix 2/3 of the olive oil with pepper and salt and coat the pork tenderloin all over with this mixture.

Heat a grill pan and grill the pork tenderloin over medium heat for 8-10 minutes until golden brown and cooked through, turning regularly for even cooking.

Finely chop the garlic and halve the chestnut mushrooms.

Heat the remaining olive oil in a sauté pan and fry the garlic and mushrooms for 5 minutes over high heat; add dried thyme for extra flavor.

Add the cranberry sauce to the mushrooms and heat everything for 1 minute. Season with pepper and salt.

Meanwhile, heat a frying pan and add the spinach in batches. Stir-fry until the spinach wilts slightly.

Drain the cooked potatoes. Add the egg yolk, butter, and a small splash of semi-skimmed milk. Season the mash with pepper, salt, and ground nutmeg. Mash everything into a smooth puree and mix in the wilted spinach.

Wash the lemon thoroughly and grate the yellow zest. This will add a fresh note to the dish.

Divide the spinach mash among deep plates and spoon the chestnut mushrooms over the top.

Slice the pork tenderloin and divide it among the plates. Serve with the remaining cranberry sauce and sprinkle everything with the lemon zest for an extra touch of flavor. Enjoy!