In a large saucepan over medium heat, combine water, potatoes, carrots, onion, bell pepper, jalapeno and garlic. Sprinkle salt and bouillon over the mixture. Bring to a boil, then reduce heat, cover and simmer 15 to 20 minutes, until potatoes are tender.
Meanwhile, in a large skillet over medium heat, cook beef until brown; drain.
Stir cooked beef and 2 cups milk into the soup and heat through. Combine remaining 1/2 cup milk with flour, stirring until smooth; stir into soup. Bring to a low boil and cook, stirring, until thickened, 3 minutes.
Reduce heat to low and stir in cheese until melted. Season with cayenne.