To Make Preserved Oranges:
Scrub oranges under running water with a stiff vegetable brush to remove any waxy coating. Trim off and discard stem ends. Quarter oranges lengthwise.
Coat wedges with salt, then pack into a 1-L jar with a lid. Press oranges very firmly into the jar to get the juices flowing. Add remaining salt and the fresh-squeezed juice from 1 orange to cover. Cover jar with a piece of plastic wrap and secure lid. Refrigerate.
Turn and gently shake jar once a day. After 1 week, oranges will be soft and ready to use. They’ll continue to develop flavour. Keep refrigerated up to 6 months.
To use, remove and discard pith and pulp using a small sharp knife. Rinse peel well to remove excess salt. Slice or dice peel. Oranges become saltier the longer they sit. Adjust the amount of peel used in recipes below accordingly.