For the lemon peel preserved in star anise and vanilla, cut the peel generously from the lemon with a knife.
Place 4 pots of water and boil the lemon peel in the 4 pots of water, one at a time, for 2-3 minutes each – this will dissipate the bitterness of the lemon peel.
Bring the water, sugar and remaining ingredients to a boil, and simmer for 5 minutes.
Pour the lemon peel into a glass jar and fill with the decoction, close tightly and store in the refrigerator for up to 6 months preserved in star anise and vanilla.