Salt and pepper the chicken, inside and out, place chicken in a large pot add water to cover the chicken. Bring to a boil then reduce heat to a gentle simmer and cook for about 90 minutes, or until chicken meat is falling off of the bone. Skim off any foam from time to time.
Remove the chicken from the pot and remove the skin and debone, return the meat back to the pot, add the squash, onion, garlic, and cumin to the pot.
Now for the tomatoes, use fresh or canned tomatoes. This is the brand I use for canned tomatoes, Brook (it is in English on the other side). There is about 4 small tomatoes in the can and it is packed with tomato juice. This a 565 gram can and cost is about 35 Baht. I would recommend using 2 cans, simply open the first can and pour into the pot, there is the whole tomatoes and about 1 cup of juice. Open the next can, drain the juice into a glass, chop the tomatoes while still in the can, very easy, drain more juice into the glass. Pour chopped tomatoes into the pot. (photo credit: Tesco Lotus Thailand)
Return the pot to a simmer to cook the vegetables. Drink and enjoy the tomato juice while the soup is simmering. Adjust salt, pepper, and cumin to taste as needed while the soup simmers, when the veggys are soft, serve.