I am not sure by any means, but my first instinct is that that the heat is to high causing separation, OR an ingredient is causing a kind of "oil and water" type of separation. Procedure or technique...
Yes, it is a chemical process.
Real cheese sauces don't reheat very well at all, they tend to break (or curdle). Reheat it slowly for better results.
nope.
beacause it does and your a bad cook
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