Peel the celeriac and cut into fine matchsticks with a sharp knife or use a Julienne peeler to make julienne strips
Blanch these in boiling water for 30 seconds then drain and rinse under cold water and pat dry on a clean tea towel
Mix dressing ingredients in a small bowl then mix these well with the celeriac and cover with cling film and refrigerate for half and hour to let the flavors develop
Serve with a sprinkling of dill or other fresh herbs of choice