Rinse the herbs, pluck off the leaves and dry them in a salad spinner or a tea towel. Place them in a blender jug with the oil and blend for a couple of minutes until the oil is green and there are no whole pieces of herb left. If you want the mayonnaise to be completely smooth, pass the oil through a fine-mesh sieve.
Place all the ingredients into the blender jug at once.
Insert the hand blender into the jug so that it touches the bottom. Then blend whilst holding the hand blender at the bottom of the jug. After a short while, you will see that the mayonnaise starts to thicken, and you can now move the blender up and down slightly. Add a little water and blend again to create a creamy, homemade herb mayonnaise.
Season to taste with salt and, if desired, extra lemon juice. The mayonnaise tastes best if it’s slightly on the tangy side, and if you make it with parsley, season it with a little freshly grated garlic. Homemade herb mayonnaise in approx. 1 min.
Refrigerate the mayonnaise immediately, where it will keep for 5–6 days.
