Chop onion and press garlic cloves.
Dice broccoli.
Add butter to Dutch Oven over medium heat. Once melted, add onions and garlic; sauté 1-2 minutes, until fragrant.
Add the rest of the ingredients EXCEPT the cheese, xanthan gum and garnish to the Dutch Oven, and bring to a boil. Once soup comes to a boil, reduce heat to LOW, and simmer for 20 minutes, or until broccoli is tender.
Once soup is cooked, add in the cheese, about ½ cup at a time, stirring to incorporate after each addition. You can add in the Xanthan Gum to thicken if you like.
Garnish with parsley or chives, and serve with additional grated cheese.