What country makes the most regato cheese?

The term "regato cheese" is not a standard cheese name. It's possible you're thinking of a specific type of cheese with a similar name, or perhaps a misspelling.

Could you please clarify what cheese you're referring to? For example, are you thinking of:

* Reggiano Parmigiano: This is a hard, granular cheese made in Italy's Emilia-Romagna region.

* Regato: This could be a regional variation of a cheese, so providing more context would be helpful.

Once you clarify, I can help you find the country that produces the most of that specific cheese.