Place a large stockpot over medium heat on the stove top. Sprinkle the bottom of pot with a pinch of salt and heat 1 minute. Add the butter and stir until melted, being careful not to let it brown or burn. This will create a nonstick effect.
Add the onion, red pepper, celery, and the garlic and cook for 10 minutes, stirring frequently. Add the chicken stock, canned tomatoes with juice, basil, parsley, thyme, and bay leaf.
Bring to a boil, then reduce the heat and simmer for 10 minutes. Whisk in the xanthan gum to help thicken the soup. Taste and season with salt and pepper. Continue to simmer (do not boil) for 10 more minutes.
Remove the bay leaf. Using an immersion blender carefully puree your tomatoes and all the vegetables and stock.
Stir in the cream to thoroughly heat.
Ladle into bowls and enjoy.
Serve with Parmesan crisps...homemade or store bought (I like Whisps)