Heat the oil in the stock pot. Add the onions and sauté gently until they are transparent and starting to take on colour.
Add the remaining vegetables, stir thoroughly and sauté for a few minutes.
Add the bouquet garnie followed by the water and bring to the boil.
Turn the heat down to a gentle simmer.
Add the salt, cover the pot and simmer for 4 hours.
Strain the stock through the sieve into the large bowl.
Allow to cool to room temperature before covering with clingfilm and placing in the fridge for a few hours.
Before using for your recipe remove from the fridge and add to your recipe.
Any stock remaining can be placed in freezer bags or pots and placed in the freezer for future use.
