Tips: Fondue with all that cheese can be a bit finicky so my fail safe back up is this: If it looks clumpy or just isn’t coming together, continue heating and stirring. It’s usually just that you haven’t gotten it hot enough. Keep it on no higher than medium heat though, don’t rush it and very importantly don’t let it boil!
If it still isn’t coming together or is lumpy you can whisk in up to 3 tablespoons of cornstarch with a bit more beer to help it come together. I start with 1 tablespoon and whisk into about ¼ of a cup of beer and slowly whisk it into sauce. Watch it for a few minutes as you continually whisk it over medium heat. Continue adding one tablespoon at a time if it doesn’t start the bind. The cornstarch will minorly alter the flavor but...it can save your evening if you need it!
Once it’s the perfect consistency transfer to your fondue pot with the flame lit and dig in right away!