Clean the leek, divide into 3 pieces each, cut in half lengthwise and wash. Cook in boiling salted water for about 12 minutes and drain. Reduce 200 ml leek stock by half. For the cheese pot, grate all cheeses or mash them with a fork. Mix with white wine, cognac and leek stock.
Season with salt and pepper. Leave to stand overnight in a well-closed container. Stir in double cream. For the vinaigrette, boil the eggs hard in about 10 minutes. Then peel and halve them. Remove the egg yolks, crush them and mix with raw egg yolk. Stir in oil, vinegar, mustard, capers and red wine. Season with salt and pepper. Wash and chop the chervil. Chop the egg white as well.
Stir in oil, vinegar, mustard, capers and red wine. Season with salt and pepper. Wash and chop the chervil. Chop the egg white as well. Stir in both. Serve vinaigrette with the leek. Arrange leek with tomatoes, mushrooms and artichokes on a plate.