In food processor finely chop cauliflower, carrots, celery, onion, and garlic working in batches if necessary.
Place large pot or Dutch oven over high heat and add the oil,chopped vegetables,salt, and cayenne. Cook until vegetables begin to soften, about 5 minutes. Add the beer and broth. Cook until the vegetables are very tender, about 15 minutes more.
Transfer the soup to blender or Food processor and purée until smooth or use immersion blender right in the pot. Return the soup to the pot and add the evaporated milk, cheddar, Worcestershire, mustard and hot sauce. Add more broth if soup is too thick and season to taste. Serve garnished with popcorn and more hot sauce and cheddar if you like.