Firstly, add the pine nuts. The reason we process them first is that they require more time and a high speed to break up properly. Once you have blended the pine nuts, add the basil leaves into the blender jug.Also, add the garlic. Start blending, at low speed (if you can adjust the speed of course), and at the same time gradually pour in the olive oil.  Add a small quantity of salt to season.Add the Pecorino sardo cheese.Add the Parmesan cheese. Now, blend again for a few seconds and then you will have your pesto sauce.

Put the pesto into a large bowl, add a spoonful of boiling water you are using to boil the linguine and then add your drained linguine into the bowl. Stir for few seconds until the linguine is evenly coated and serve.

If you like, sprinkle with freshly grated Parmesan cheese.