Melt butter in a saucepan over medium heat. Add onion & celery. Cook until softened, 3-4 minutes. Stir in garlic and cook just until fragrant, about 30 seconds.
Add potatoes and chicken broth. Cover and simmer 8 minutes.
Add broccoli and cook until softened, about 5-6 minutes.
Remove 1 cup of broccoli and potatoes and slightly chop. Set aside.
Using a hand blender, blend remaining soup in the pot until smooth. Add cream and simmer 1 minute. Stir in reserved broccoli, potatoes, and cheeses.
Garnish with additional cheese if desired.
