Beer and Cheese Soup

1 cup carrots, chopped
1 cup celery, chopped
1 cup yellow onions, peeled and chopped
2 teaspoons salad oil
6 cups chicken broth
1 cup cheddar cheese, grated
2 teaspoons flour
salt and pepper to taste
1 teaspoon dry mustard
1/4 teaspoon Tabasco
1/2 teaspoon Worcestershire sauce
1 12-ounce bottle beer
Polish sausage or knockwurst (optional)

Saute the carrots, celery, and onions in the oil until lightly browned. Bring the broth to a boil, add the vegetables, and simmer for 45 minutes. Dredge the cheese in the flour, and mix into the soup, stirring constantly until the mixture thickens. Keep stirring often until you serve. Add the seasonings, mustard, Tabasco, and Worcestershire. Finally, add the beer, and stir until all is hot. You may add sliced cooked sausage to this just before serving, if you wish.