This is my second time baking these. I did my first fold then let the dough rest overnight. This morning the dough smelled sour- I think it's overproofed? Is it possible to save this? I don't like the sour taste in croissants. Or is the dough essentially ruined?

Regarding the butter- I'm using American butter because that's all I could find, but given all I've read, I will use a European butter next time. Sounds like the higher fat content really helps the butter to not break. The higher water content of a typical American butter makes it difficult to keep the butter and dough at similar temps. The butter remains a bit harder and so easier to break than if water wasn't present. It's a learning process!

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