Place the lavender in the sea salt overnight to infuse. Put flour, lavender salt, table salt, egg whites and water into a bowl and mix together, place the dough into a refrigerator to rest for at least 2 hours. Sear the partridges in a hot pan on all sides, baste with the butter and season well. Roll out the salt dough and wrap each partridge in the salt dough. Bake for 30 minutes at 180ºC.