This guide is for capturing encrypted web traffic between the Internet and a 3DS or Wii U. You will need a hacked console for this.
NOTE: This traffic is sensitive - it will likely contain sensitive data such as a hashed form of your NNID password, and the device's unique identifiers including their unique certificates - as such, please be careful who you share these dumps with! They should be stored safely.
Dumping TLS traffic requires a proxy - we suggest mitmproxy which is both FOSS and cross-platform. It also has a web view which is useful for saving the recorded data (though this can also be done via CLI, as explained later).