Cuisine update guide :
WhateverOS (but using Chrome navigator):
1) Go to the web flasher page here
2) Plug in your Cuisine.
3) Press "Update" to flash it with the latest version.
4) Select the current serial port of your Cuisine.
5) Wait until the button shows "Update Done"
6) Let's get cooking!

Alternativaly you can upload an older or alternative firmware (please, only upload .hex file design specificaly for Cuisine as doing otherwise would void your warranty).
Release History
Ressources for developing you own sequencer on Cuisine's hardware can be found here :
https://github.com/Floating-Knobs/Cuisine_Hardware/tree/main

If you are a command line jedi here is the avrdude command for uploading :
"avrdude -c arduino -D -b 115200 -p atmega4809 -P \"{port}\" -U flash:w:{hex_file_name}:i"