Trim the cauliflower and discard any wilted leaves, then roughly chop the florets, stalk and remaining leaves. Heat the oil in a large, deep saucepan over a medium heat, tip in all the cauliflower pieces, the onion, celery, garlic, thyme and a large pinch of salt, cover partially with a lid and cook for 15-20 mins until all the vegetables have softened.

Tip in the potatoes, milk and stock, and bring to a simmer. Season well with black pepper, then continue to simmer for 15-20 mins, partially covered, until everything is fall-apart tender. Remove from the heat and discard the thyme. Blitz until smooth using a hand blender, then return to a low heat and stir in the cheese until fully melted. Season and add a splash more stock or milk if it’s too thick. Will keep chilled for up to three days, or frozen for two months. If travelling, decant into a heatproof flask.

To make the croutons, heat the oven to 190C/170C fan/gas 5. Tip all the ingredients onto a large baking tray and toss together using your hands. Season and bake for 15-17 mins until golden. Leave to cool completely on the tray. Will keep in an airtight container for up to three days. Sprinkle a handful of croutons over the soup or into the flask just before serving.