Wash organic lemon hot, grate dry and roughly grate the peel. Put the lemon grated in cold water and chill. Halve both lemons and squeeze the juice.
Wash the pears and rub dry. Cut into wafer-thin slices with a slicer or slicing machine at the smallest setting. Spread pear slices on 4 baking trays lined with baking paper and sprinkle with lemon juice.
Wash the thyme, shake dry and pluck the leaves from the stalks. Sprinkle pear slices with thyme and salt. Leave to dry in the preheated oven (electric cooker: not recommended/ circulating air: 100 °C/ gas: not recommended) for approx. 1 3/4 hours. Let the pears cool down on the baking tray. Drain lemon zest, dab dry and sprinkle over the pears. Store pears in a cool, dry place.