To assemble the instant soups, set out four heat-safe jars that can accommodate about 20 fluid ounces in volume (I used 19.6-ounce straight-sided Weck jars). In each jar, layer the ingredients in the following order: 1/2 cup spinach leaves, 1/4 cup shredded carrots, 1/2 cup tofu or chicken, 1/2 tablespoon miso paste, 1 teaspoon soy sauce, one nest of softened noodles, 1 tablespoon bouillon powder and, finally, scallion greens to taste (at least 2 tablespoons). Cover and store in the refrigerator until ready to serve.