Whisk together flour and 1/4 cup chicken broth in a small bowl then set aside.
Saute bacon in a large soup pot over medium heat until crispy. Using a slotted spoon, transfer bacon to a paper towel-lined plate. Drain all but 1 Tablespoon drippings from the pot.
Add onion, celery, and garlic to the pot. Season with salt and pepper and saute until vegetables are tender, about 4-5 minutes.
Add cauliflower to the pot then stir to combine.
Add water then place a lid on top. Steam cauliflower until tender, stirring a couple of times, about 5-7 minutes.
Add remaining 1 3/4 cups chicken broth and milk. Turn up the heat and bring to a boil.
Slowly whisk in flour/chicken broth mixture while constantly stirring. Then turn down the heat and simmer for 3-4 minutes, or until chowder has thickened.
Turn off heat and stir in 2 cups cheddar cheese until melted and smooth. Then stir in half of the cooked bacon.
Check the seasoning and add salt, pepper, and hot sauce to your taste.
Serve warm topped with remaining shredded cheese, cooked bacon, and some green onion.