I use Shelton's Low-Sodium Chicken Broth. The only things it contains are Chicken Broth and some seasonings. No Salt, No MSG, No Sugar, No Trans-Fat. You can also make your own by boiling Chicken in Water. One nice Soup is:

2 cans Chicken Broth
12 fl. oz. Water
8g Olive Oil
240g Cooked Light Meat Chicken
60g Keto Spaghetti
20g Darielle Fusilli Pasta
1/8 tsp Garlic Powder
1/4 tsp Lite Salt
Pepper to taste
1/2 tsp Xanathan Gum
80g Shredded Mild Cheddar Cheese

Pour the Chicken Broth and Chicken into a pot [on the stove] and cook at medium, stirring constantly. After the Broth begins to turn color, add the Water, Olive Oil, Pastas, and Seasonings. Continue stirring until the Pasta reaches desired consistency. Remove from heat and stir in Xanathan Gum. Add Cheese and eat.

Makes 2 large servings.