I reside in Germany and have an Aufenthaltstitel.
During the Visa process for working in Germany, my employer obtained a special authorisation from the Bundesagentur für Arbeit (Federal Agency for Work) that made proving my work experience unnecessary.
However, now I wish to change companies, and according to the German Ausländerbehörde (Foreigners Authority), I need to provide "comparable qualification that you have acquired through at least three years of professional experience during the past seven years".
However in my country (Brazil) we don't have Arbeitzeugnis (Recommendation Letters) like in Germany, we use a government issued document for documenting experience. The Ausländerbehörde said it's risky giving just that one and told me to "try to get the letters just in case". They told me they can't provide any sample, though, and I also came empty handed after asking expat relocation agencies.
Some of my previous employees overseas have agreed to sign a document proving I worked, as long as it's not a "recommendation" per se, since my previous managers are long gone at this point.
Does anyone know of how such document should be structured, or if there's anything else I can use instead?