I made an alfredo sauce last night using a roux made with ghee instead of regular butter, since that's what I had on hand. The ingredients were: ghee, flour, heavy cream, garlic, pecorino romano, and salt and pepper to taste.
The sauce turned out great, I was able to get the consistency to exactly how I wanted it.
When I went to reheat it in the microwave at work today for lunch, the sauce separated terribly, essentially leaving a pool of butter in the bottom of the bowl. It tasted ok, but it definitely felt like I was eating spoonfuls of butter at times. If it matters, the sauce and pasta were combined before microwaving, I didn't reheat the sauce by itself.
Is there a trick to reheating a homemade alfredo/béchamel sauce that will keep it from separating in the microwave? As suggested in this thread, could I add an emulsifier that will help the next day, but won't negatively affect the taste or consistency of the dish when it's still fresh?
Note: I posted this as a separate question from the one I reference above because this is specifically about separation during reheating, not storage, which might have different answers (such as lower temp or less time).