Vegetable Cheese Soup

2 cups diced potatoes
1 cup diced carrots
1 cup diced celery
1 onion diced
2 (10 ¾ oz.) cans chicken broth
2 teaspoons or 2 cubes chicken bouillon
¼ cup butter
½ cup flour
2 cups milk
1 tsp dry mustard (I don't think you'd miss it, if it's not in your cupboard)
3 cups grated cheddar cheese

In a large saucepan, combine diced vegetables, butter, bouillon, and broth together. Simmer on medium-low heat for 30 minutes or until vegetables are tender. In a medium bowl, gradually mix milk with flour; blend until smooth. Gradually add milk mixture to vegetables, stirring constantly. Add grated cheese and dry mustard. Simmer and stir until cheese melts.