Clean and peel the carrots and coarsely grate them on the vegetable grater. Mix the grated carrots with the lemon juice. Wash the herbs and shake dry. Cut the chives into small rolls and finely chop the parsley leaves.
Mix the sour cream with half of the grated carrot and half of the herbs, season with curry powder, pepper and sea salt.
Spread the carrot cream on the bread and garnish with the remaining shredded carrots. Scatter the remaining herbs and the chopped walnuts on top.