Make sure the ingredients are at room temperature. Mix the egg yolk with the salt, the pepper, half a teaspoon of quince vinegar and 1 teaspoon of apple balsamico mustard. Use an electric hand mixer.
With the hand mixer, mix in the pumpkin seed oil, first only in drips and then gradually increasing the volume until it becomes a thick pulp.
The mayonnaise thus prepared should be consumed on the same day. Raw egg yolk can be replaced with the grated yolk of a boiled egg, and then be stored in the fridge for several days for consumption.