Roast the beef bones at 190C for 30 minutes. While roasting, heat up your slow cooker on high.

Once roasted, place the bones in your slow cooker along with the boiling water.

Add the potato peelings, onions, garlic, kelp seaweed and nettle tops.

Simmer in the slow cooker on low for between 6-8 hours, longer if you want a stronger flavour.

Sieve out the bones and plant matter and store in a refrigerator until ready to use, or drink straight away.