Wash the greens
Wash and dry the green (basil, parsley, mint, and spinach) using a salad spinner.
In a blender blend together the greens, Pecorino Romano cheese, peeled garlic cloves, olive oil, lemon juice, and pine nuts (or other nuts). Add the ice cubes - they will prevent the oxidation and preserve the beautiful green color. Pulse a few times to get a creamy Spinach Basil Pesto Sauce. Season to taste with salt and pepper.
Serve or store
Transfer your pesto to a bowl or a glass jar. Add a tablespoon of olive oil on top of the pesto in a jar to cover the pesto. Store in a fridge for up to a week or use immediately on pasta, salad, fish, meat. You can also freeze the pesto in ice cube molds to have your pesto ready any day of the year. Keep it frozen for up to 2 - 3 months.TipTo prevent the oxidation, cover the glass jar in aluminum foil (the exterior of the jar).