- 5 Potatoes (about 400 grams)
- 1 ounce Walnuts
- 1 piece Celery root (about 200 grams)
- ½ Lemon
- 1 tablespoon walnut oil
- 1 tablespoon Olive oil
- Tabasco sauce
- 2 Eggs
- 2 teaspoons Truffle oil
- 2 tablespoons Whipping cream
Peel potatoes and cook in a pot of boiling salted water until fork-tender, about 20 minutes.
Meanwhile, chop the walnuts coarsely and toast in a pan. Transfer to a plate and let cool.
Peel the celery root, cut into thin slices and cook in another pot of boiling salted water for 1 minute.
Drain the celery root, rinse with cold water and drain well. Squeeze juice from lemon half.
Mix the celery root and walnuts in a bowl with 1 tablespoon lemon juice, the walnut oil and olive oil. Season with salt, pepper and a little Tabasco. Set aside.
Drain the potatoes well, then press the warm potatoes through a potato ricer into a bowl.
Separate the eggs. Whisk the egg whites with a pinch of salt until stiff.
Whisk the yolks with 1 teaspoon truffle oil and the cream. Mix yolk mixture into the potatoes. Season with salt, pepper and a pinch of freshly grated nutmeg.
Fold the whipped egg whites into the potato mixture.
Brush 2 large cups with the remaining truffle oil. Divide potato mixture between prepared cups. Bake on the bottom rack of preheated oven at 200°C (fan oven: 180°C, gas: mark 3) (approximately 400° F) until puffed and golden on top, about 20 minutes. Garnish celery-root salad with mint and serve alongside soufflés.