1. Wash cabbages and remove any wilted or bruised outer leaves. Cut into quarters and remove core. Slice very thin and transfer to a large bowl; toss with salt and let mixture sit for 15 minutes.
2. Using clean hands, thoroughly knead and massage cabbage and salt together until cabbage softens and releases juices, 5 to 10 minutes. Mix in apples and fennel seeds. Transfer cabbage mixture and liquid to a wide-mouthed 2-quart jar or ceramic crock, packing mixture down firmly with hands to fit and compress any air pockets.
3. Cut a piece of parchment paper into a circle wide enough to fit flush inside the jar. Fit paper on top of cabbage mixture (this will help keep stray pieces of cabbage submerged). Fill a second jar, small enough to fit inside of the larger one, with water. Seal it and place on top of parchment paper to act as a weight. Cover large jar with a clean kitchen towel and secure with a rubber band.
4. Place in a cool, dark place, such as a cabinet. Every few hours, press down on weight to force cabbage mixture to release more of its juices. After 24 hours, cabbage mixture should be completely submerged within brine. If not, create more brine by dissolving 1 teaspoon salt into 1 cup water and add to cabbage mixture until completely submerged.
5. Check sauerkraut every few days, skimming off any white foam that may appear on the surface and making sure cabbage mixture stays submerged in brine. Taste after 1 week, and then every few weeks until desired flavor and consistency is reached.
6. To store, remove small weighted jar and parchment paper, seal jar with lid, and refrigerate for 6 months to 1 year.
Source: Hannaford fresh Magazine, March - April 2017