Preheat your oven on its lowest setting ( usually 80 degrees C / 175 degrees F).
Peel the bananas and discard the skin.
Squeeze the juice from the lemon and brush over the bananas.
1 juice Lemon
Put the silicone baking mat in your baking sheet tray with the pyramid side up.
Spread out the banana slices on the tray.
Put in the oven for 1 hour.
Test the slices. They should be spongy but not crispy. If they are still soft, leave them in the oven for another 1/2 hour and test again.
Once done, remove and allow to cool.
Store in an airtight container for up to 4 weeks