In a Dutch oven, combine the cauliflower, carrot, celery, water and bouillon. Bring the mixture to a boil. Then, reduce the heat. Cover the Dutch oven, and simmer for 12 to 15 minutes or until vegetables are tender. Do not drain the liquid.
In a large saucepan, melt the butter. Stir in the flour, salt and pepper until smooth.
Gradually add the milk to the saucepan. Bring the mixture to a boil over medium heat. Cook and stir for two minutes, or until thickened.
Reduce the heat. Stir in the cheese until melted. If desired, add the hot pepper sauce.
Stir the cheese sauce into the cauliflower mixture.
