Cook the frozen peas and scallion in the boiling water with the stock concentrate or stock cube until tender and cooked through. Remove and discard the scallion once the peas are soft enough to be blitzed into soup.

Chop up the mozzarella roughly and put it into the blender – or a processor, but soup is always more velvety when processed in a blender – with the peas and their liquid. I do this in about three batches, pouring the vilely green and – it’s true – slightly slimy soup back into the pan and heating gently to meld cheese and peas better together. Otherwise just set aside and reheat later.