Mayonnaise

1 egg yolk

½ teaspoon mustard powder

½ teaspoon salt

A twist/pinch of white pepper

½ teaspoon sugar

1 tablespoon lemon juice (or white wine vinegar)

150ml vegetable oil (or light olive oil)

Put the egg yolk in a small food processor (or bowl, if you’re feeling brave) with the mustard, salt, pepper, sugar and lemon juice (or vinegar). Whisk/blend, adding the oil in a fine stream (if you’re using a blender) or drop by drop (if you’re doing it by hand) until the mix thickens. If there’s still some oil left, add a little warm water and that will slacken it. Keep going until the oil is used up.