In a large pot, brown the turkey bacon until crispy, remove and set aside for garnish.
In the same pot, combine 3 cups chicken broth, potato pieces, and cauliflower florets.
Bring to a boil, then simmer until vegetables are very tender.
Use an immersion blender to puree the potato-cauliflower mixture until completely smooth.
In a separate skillet, melt butter over medium heat; add diced onion and cook until translucent.
Add minced garlic and flour to the onions, cooking for 1 minute to remove the raw flour taste.
Whisk in the remaining 2 cups of chicken broth and half and half, stirring until thickened.
Pour the creamy onion mixture into the pureed vegetable base.
Add the broccoli florets, diced carrots, and bay leaf.
Simmer for 10-12 minutes or until broccoli and carrots are tender but not mushy.
Remove the bay leaf, stir in the shredded cheddar until melted, and season with salt and pepper.
Serve warm, topped with the reserved crispy turkey bacon.