Jamie's Chicken Salad Sandwich

First, using a medium sized stock pot, boil your eggs with salt. Using a large stock pot, place the chicken along with the salt, pepper, onion, and celery stalks. Boil chicken until well done and reserve stock. Remove chicken from pot, cool, and remove skin and bones. Dice the chicken and in a large bowl, combine with the chopped celery, eggs, a spoon full of stock, and remaining ingredients and mix well. Slice the bread, onions, and tomatoes. Layer the onions, tomatoes, spinach, and chicken salad between two slices of bread and serve.