Peel the carrots and cut into small pieces. Peel the potatoes and cut them into small pieces. Peel and chop the onion.
Cook the carrots, potatoes and onions in 2 liters of vegetable stock until cooked. Add the cream and grind with the hand blender. Season with salt, pepper and a little garlic.
Arrange in plates, put the chopped walnuts in the middle, sprinkle with chives and top with champagne on the edge (depending on taste).