Dice tomatoes and garlic and puree in a blender. Crush the hazelnuts in a mortar and add to the tomato paste. Slowly add the olive oil. Mix everything well until you get a creamy paste. Chop the basil leaves and parsley and mix in. Possibly season with pepper and let it steep for at least 2 hours.
The pesto tastes very good with spaghetti. If you like, you can add a few roasted pine nuts.