This bright, healthy spinach pesto will keep you energized through the cold months until summer, when the basil pesto rules. Spinach is 50% protein by calorie, one of the many unsung plant sources of "lean protein." Fresh lemon juice transforms this cool-weather pesto into a silver-medal winner. It's thrifty, easy, and healthy as well as being downright craveable. Using "nooch" instead of Parmesan cheese makes this pesto vegan, low-fat, and cholesterol-free.