Wrap the beetroot in foil and place on a tray in the oven until tender, about 40 minutes.
When cool enough to handle, peel beetroot and chop coarsely.
Chop gherkins and herbs.
Arrange mixed leaves, beetroot, gherkins and chunks of cheese on plates or a platter. Sprinkle with herbs and pistachios. Drizzle with balsamic and olive oil and season with salt to taste.