Set a Dutch oven, or other heavy bottomed soup pot, over medium heat. Add the butter to melt, then stir in the onion and cook until softened- roughly 5 minutes. Stir in the garlic and cook for 60 seconds.
2 tbsp butter, 1 yellow onion, 3 garlic cloves
Add all of the seasonings and the chopped zucchini to the pot. Stir and cook for 5 minutes.
1/4 tsp dried rosemary, 1/4 tsp dried thyme, pinch dried oregano, 1/4 tsp celery salt, salt & pepper, dash cayenne pepper, 5 cups fresh chopped zucchini
Add the potatoes, broth, and soy sauce to the pot. Stir everything together to evenly combine and bring the soup to a boil, then immediately reduce the heat to medium.
3-4 cups chicken broth, 1 tbsp soy sauce, 1 lb russet potatoes
Simmer, partially covered, for 15-20 minutes, just until the potatoes and zucchini are both fork tender.
Remove the pot from heat and use an immersion blender to puree until the soup's smooth. Add the cream and cheese, stirring until melted and evenly combined.
1/2 cup heavy cream, 1 1/4 cup shredded cheddar cheese
Ladle into bowls, serve warm, and enjoy!