For the sandwich
- 4 slices of white bread, soft
- 4 eggs, at room temperature
- chives, about 1 heaped tablespoon, finely chopped
- white pepper
- malt vinegar
For the mayonnaise
- 1 egg yolk
- groundnut oil, or vegetable oil
- 1 tsp white wine vinegar
- 1/2 tsp mustard powder
- Put the eggs in a saucepan and cover with cold water. Bring to the boil then simmer for 6 minutes. Place in a bowl of cold water.
- Make your mayonnaise. By far the easiest way to do this is by using an electric mixer with a whisk attachment, but it’s perfectly possible by hand.
- Put the egg yolks in a clean bowl and whisk them together. Whisk in the mustard powder. Begin adding oil a few drops at a time, whisking as you do so and making sure each bit of oil is fully incorporated before adding the next.
- As you whisk in more oil and the mayo starts to thicken, you can start adding it in very slightly larger quantities until you are steadily adding it in a thin stream. If it splits, don’t despair. Take a fresh egg yolk in a clean bowl and begin adding the split mixture into it, very slowly, just as if it were the oil. This should bring it back. Add the white wine vinegar and season with salt.
- Peel the eggs, and mash them with a fork. Mix in 2 tablespoons of the mayo and the chives, then season with salt and white pepper. Add a teaspoon of vinegar to start with, adding more if you think it’s needed. Spread the mixture onto one slice of bread, top with the other, and cut into preferred sandwich shape.