Buy a bag of spinach at the supermarket, toss 3 cups of it in a bowl with 2 tablespoons of olive oil, 1 tablespoon of vinegar (any kind you like), and salt and pepper, and top with a handful of crumbled feta cheese and toasted nuts. (It’s okay, and good, to mix some protein and fats into your green starter.) You can also add pesto, grated parmesan cheese, and some toasted seeds,