Melt butter, mix in the flour and cook for at least two minutes. Add the chicken broth a bit at a time, constantly whisking until all is added. Bring broth mixture to a boil and reduce heat to simmer, add cheese in small amounts, whisking to melt and blend. Continue until all cheese is added. Simmer for a few minutes and transfer to a fondue pot. Light a sterno under the fondue pot and serve with cubes of french bread for dipping. Per Serving (excluding unknown items): 563 Calories; 45g Fat (72.5% calories from fat); 29g Protein; 9g Carbohydrate; trace Dietary Fiber; 140mg Cholesterol; 783mg Sodium. Exchanges: 1/2 Grain(Starch); 4 Lean Meat; 6 1/2 Fat.