In a tall, narrow container (it should be just wider than the head of the hand blender) combine one egg, lemon juice, vinegar, GIA garlic paste, a big pinch of salt, and extra virgin olive oil.
Blend briefly to mix, then add half of the sunflower oil and blend again.
Continue adding oil slowly and blending until the mayonnaise is ready, creamy to the desired point (it may not be necessary to add all the oil).