Mustard kippers

Boil the kippers in the bag, for 6 mins or as directed.

Remove the bag from the pan carefully, with tongs. Set aside on a plate, still in the bag.

Throw away the fish cooking water, pour fresh boiling water into the pan and bring to the boil. Add a dash of vinegar and stir with a spoon to create a whirlpool.

Crack eggs into pan and simmer for 3-4 mins.

Meanwhile, pile the spinach into a large pan, without adding any extra water, and cook over a medium heat for about 4 mins, turning it occasionally, until wilted.

Tip the spinach into a colander. Push it down with a spoon, chop it roughly with the spoon and add the knob of butter.

Spoon the spinach on to two warm plates.

Snip the bag of kippers and pour the buttery juices into a small bowl or jug. Put the kippers on the spinach, top with an egg, then whisk the mustard into the buttery juices and spoon over the egg. Serve with tomatoes.