How to make bone broth

Ingredients

• 2 kgs of bones
• At least 3 litres of filtered water (plus extra to top up during slow cook)
• 2 tablespoons of apple cider vinegar (preferably choose a variety that still has the ‘mother included)
• 2 carrots cut into quarters
• 2 stalks of celery
• 1 brown onion cut into half
• 4 garlic cloves
• 1 bay leaf
• Half a dozen sprigs of thyme