Egg yolks, oil, mustard. The universal binder — everything else in this list starts here.
Debate rages about whether the sauce comes from Mahón in Menorca or from a French chef's improvisation in the 1750s. Doesn't matter. What matters: made properly, from scratch, mayonnaise is a revelation. Shop-bought is a compromise the French will never forgive you for.
Bring 2 egg yolks to room temperature — cold yolks refuse to emulsify. Whisk with 1 tsp Dijon and a pinch of salt.
Add 250ml neutral oil (sunflower, grapeseed) DROP BY DROP at first, whisking hard. After the first two tablespoons, thicken up and pour in a thin, steady stream.
Once you have a thick, pale, glossy mayonnaise, whisk in 1 tbsp white wine vinegar or lemon juice. Taste and adjust salt.
For the modern robot version: same ingredients into a jug blender, blitz until thick. Takes twenty seconds and works every time.