How to cache with HTTPS?
If your scale actually makes caching worth it you can run a local HTTPS mirror. If you don't control the endpoints to do that, you don't get to MiTM anything.
https://wiki.squid-cache.org/Features/SslPeekAndSplice
give the cache server a certificate?
SSL bumping
If your scale actually makes caching worth it you can run a local HTTPS mirror. If you don't control the endpoints to do that, you don't get to MiTM anything.