Heat the oven to 200°C (400˚F). Scrub the beetroot thoroughly and wrap each one in aluminum foil. Place on a rack in the oven and roast for 20 to 50 minutes, depending on size. When you easily prick through them, they are done.
Let the beets cool slightly and peel off the skin. Cut into pieces.
Pick all the herbs.
Make a vinaigrette from the mustard, vinegar and oil.
Rinse the lentils under the cold tap and drain.
Scramble the lettuce, chicory, green herbs and watercress with the vinaigrette and mix in the lentils and beet.
Place in a pretty bowl and sprinkle with the chopped nuts