Romano cheese Place spinach, pine nuts, garlic, and 1/4 to 1/2 tsp. of salt, if desired, in a food processor fitted with the steel blade or a blender jar. Pulse several times to begin chopping and blending the ingredients. Then turn on machine at high speed and pour in the olive oil in a steady stream. Blend until the mixture is a smooth paste. If you are using a blender you will have to stop and start the machine occasionally to give the ingredients a stir. When the ingredients are pureed, transfer to a bowl and stir in the cheeses. Blend thoroughly. For parsley pesto, substitute 2 c. of parsley for the spinach.