1. In a large soup pot, melt the butter over medium heat. Add the diced onion and sauté until translucent. Add the garlic and cook for 1 minute more.

2. Sprinkle in the flour and stir continuously to create a roux. Cook for 2-3 minutes.

3. Gradually whisk in the chicken broth, ensuring the mixture stays smooth.

4. Add the diced potatoes and bring to a boil. Reduce heat and simmer for 20 minutes or until potatoes are fork-tender.

5. Use a potato masher for a chunky soup or an immersion blender for a creamier texture.

6. Stir in the heavy cream and shredded cheddar cheese. Mix until the cheese is fully melted and incorporated.

7. Season with salt and pepper to taste.

8. Cook the bacon in a separate skillet until crispy, then crumble and set aside.

9. Ladle soup into bowls and top with sour cream, crumbled bacon, shredded cheese, and green onions.