Over a medium heat and with a spritz of Frylight sauté the garlic, onion, celery and potato for 5 minutes.
Add boiling stock and milk. Bring to the boil, cover with a lid and allow to simmer over a medium heat for 10 minutes.
Stir in half of the spinach, a pinch of Black pepper, cover and simmer for a further 10 minutes.
Place into a blender or Nutribullet with the remaining spinach and blend until smooth.
Place back into the pan for 2 minutes over a medium heat stirring constantly to reheat.