I recently updated my dev machine (Macbook Pro) to macOS Big Sur version 11.1. After upgrading, I encountered this error after running npm run dev on one of my projects.

Here's a quick fix that worked for me..

Make sure you are using the LTS version of node. You can get it from nodejs.org (version 14.15.4 as of this writing).

Run npm rebuild node-sass --force command.

And you should be good to go!