Wash and scrub the celeriac thoroughly. Cut off the root so that the celeriac bulb can stand on a flat surface. Put on baking paper, rub with oil and salt and cook in the oven at 180 degrees for about 2 hours.

Wash the potatoes with their skins on, also put them on the baking paper and cook in the oven for about 1 hour until they are tender. In the meantime, prepare the cognac-pepper-cream sauce.

For that finely dice the shallot. Sauté colorless in a pan over medium heat with a little olive oil. Deglaze with the cognac. Let it boil down briefly. Add vegetable stock, vegan cream, pepper corns and paprika powder. Season with salt and simmer for 5 minutes at a slightly higher temperature. Mix the cornstarch with a little cold water and stir into the sauce. Let it boil for another 1-2 minutes before serving.

Press the hot potatoes through a potato press (alternatively peel and mash them). Heat the vegetable milk together with the vegan butter. Mix the potatoes with it. Season the mashed potatoes with salt, pepper and nutmeg.

Take the celeriac out of the oven. Serve sliced ​​with the mashed potatoes and creamy cognac pepper sauce. Sprinkle with chopped walnuts if you like.