For the celeriac, bring a pot of salted water to a simmer and then cook the celeriac until tender but not soggy. Drain well

Use a potato masher to crush the hot celeriac with the butter, a pinch of white pepper and salt to taste. Keep warm until needed

Preheat the oven to 170°C/gas mark 3. Place a generous spoonful of the celeriac into each serving dish, make a well in the centre large enough to hold an egg. Add the egg and top each with a tsp of cream and butter. Place in the oven for approximately 8 minutes, or until the egg is cooked to your preference - the egg should be runny enough to sauce the dish

Meanwhile, heat the vegetable oil over a medium heat, and once sufficiently hot - around 180°C - fry the celery leaves until crisp. Drain well on kitchen towel and season with salt

To serve, top each egg with the crispy celery leaves, croutons, Madeira sauce and a slice of truffle. Season and serve immediately