Have a bowl full of cold water acidulated with the juice of 1 lemon standing ready; peel the Jerusalem artichokes and immediately drop into the water to prevent discoloration. This stage of the preparation can be done in advance.

Shortly before serving, slice the drained and dried raw artichokes very thinly on a mandoline cutter or in your food processor. Spread out the slices, overlapping one another, on individual plates; season with salt, freshly ground pepper and sprinkle with a little olive oil and lemon juice.

Cut the lemon slices in half and arrange some on each plate, in a fan shape. Serve immediately.