Pre-heat oven to 200 degrees Celsius.

Put the stock in a large pot. Get a bit of string, then firmly tie the rosemary, thyme, bay leaves and onion together and add to the pot. Start heating the stock up on the lowest heat possible. The onion and the herbs will slowly infuse in the stock.

Line a baking tray with baking paper. Put the Cauliflower, leeks, your garlic clove, half of your olive oil and a good pinch of salt and pepper in a large bowl. Mix together until all the ingredients get coated evenly in the olive oil, then put them on the tray. Make sure everything is spread out evenly, if it is all piled on top of one another, the ingredients will steam rather than roast. Cook on the oven for 30-35 minutes.

Once your cauliflower, leeks and garlic have been roasted, it's time to take the tied up aromatics out of the stock. Take your roasted garlic clove, remove the skin and put the flesh in a blender, along with your cauliflower, leeks, milk, mint leaves and ladle in about half of your stock as well. Blend for 1-2 minutes until smooth, then add to the pot with the rest of the stock and mix through. Alternatively, you could just put those ingredients in with the stock and use a hand blender.

Bring the soup to a boil. Once boiling, turn the heat down and simmer for 10-15 minutes stirring occasionally.

Meanwhile, get a frying pan on medium heat, then add your olive oil. Make sure the oil is nice and hot before adding the bread, otherwise you can end up with soggy and oily croutons. Add the bread and fry for about 5 minutes turning every so often in the pan. Once the croutons develop a nice golden brown colour, add a good pinch of salt, then turn the heat off.

Once the soup is done, serve in appropriate bowls, then garnish with the croutons and shredded basil. Enjoy!