Chop 2 medium size potatoes in small cubes ( if you're on a diet, use courgettes instead) as well as one medium onion. Add 3 medium carrots and also chop into cubes. Add 2 pints of water, 2 table spoons of olive oil and sea salt to taste. Boil the vegetables together until they are mushy and then blend them into a creamy soup.
The final touch is adding the spinach - 500gr to 1 kg depending how "spinachey" you would like.