Chop the cabbage with a knife or you could use the chopping action on a food processor if you have one. Place shredded cabbage into a bowl.
Chop up the white onion and place into the bowl with the cabbage.
Chop up the celery and place into the bowl with other ingredients.
Chop the peppers and place into the bowl with other ingredients.
Add the sea salt to the bowl and stir in well.
Next make the dressing by stiring into a jug the olive oil, apple cider vinegar, celery salt, black pepper, and mustard powder. Once these have been stirred together well pour into the bowl with other ingredients and mix together well. Place into this mix the Goji berries if you wish to use them.
Leave ingredients in the bowl to marinade for 1-2 hours. Sieve off the remaining liquid and keep in a jar for the next batch you make. Put the Kali's slaw into a jar and keep in the fridge, use within 4-5 days.