Heat a large stockpot or Dutch oven over medium heat. Add bacon and cook until brown and crispy, about 6-8 minutes. Transfer to a paper towel-lined plate; set aside.
Melt butter in a large stockpot or Dutch oven over medium heat. Add garlic, onion, carrots and celery. Cook, stirring occasionally, until tender, about 3-4 minutes. Stir in cauliflower and bay leaf. Cook, stirring occasionally, until barely crisp-tender, about 3-4 minutes.
Whisk in flour until lightly browned, about 1 minute. Gradually whisk in chicken broth and milk, and cook, whisking constantly, until slightly thickened, about 3-4 minutes.
Bring to a boil; reduce heat and simmer until cauliflower are tender, about 12-15 minutes; season with salt and pepper, to taste. If the chowder is too thick, add more milk as needed until desired consistency is reached.
Serve immediately, garnished with bacon and parsley, if desired.
4 slices bacon, diced
2 tablespoons unsalted butter
2 cloves garlic, minced
1 onion, diced
2 carrots, peeled and diced
2 stalks celery, diced
1/4 cup all-purpose flour
4 cups chicken broth
1 cup 2% milk
1 head cauliflower, roughly chopped
1 bay leaf
Kosher salt and freshly ground black pepper, to taste