Add butter, garlic, onion and cauliflower to a large pot and saute for 5 minutes until cauliflower starts to brown.
Add flour, chicken bouillon, ground mustard, paprika, salt and mix well, then add 2 cups milk and stir. Reduce heat and boil for 10 minutes, cauliflower should be soft.
Add to a blender and blend until smooth.
Transfer back to the pot and add the rest of the milk.
Add parmesan cheese, cheddar cheese and stir until melted.When cheese is melted and its heated through, serve in bowls and top with bacon, croutons and extra cheese.