Add the basil leaves, garlic (peeled and cut in half), salt, pine nuts and oil to a container suited for the immersion blender.
Start the immersion blender. At the beginning it may be slightly difficult to use due to the various textures. But as the pine nuts break down and the oil blends in the mixture will loosen.
Add the grated cheese and give a final blend until smooth.
Notes
If you're using home-grown or ecologic basil you don't need to wash it, but if you are unsure or it's a bit soiled you can rinse the leaves and dry through a salad spinner or by gently patting them dry between two towels.
If the blender gets stuck just remove the obstruction with a spoon, put it back into the container and start again. An up and down motion with the blender can be very helpful before the mixture loosens.
Store pesto refrigerated in a closed jar topped with a half cm olive oil. Consume within 2 days. For longer shelf life freeze up to 2 months.
The sealing layer of oil on top prevents the pesto from oxidizing and turning dark. Add it as soon as possible to minimize exposure to air. Do not add lemon juice to prevent oxidization as there is no way to hide its strong flavour.
Please notice that the nutritional information provided is made by an online calculator and meant to be used as a guideline only.