I am currently recreating my portfolio, which is powered by a node/express backend. I want to have some pages where I can update/add projects to my portfolio, and I know that I will be the only admin on this site. I want to protect these pages with admin credentials. I think a user table on my database (mysql) is overkill though... is it a good idea to store user/(hashed)pass in process.ENV? I feel like theres a better way.
A database can be anything, text file, sql db, json file, even a variable in your program. A database it's just something which store data.
So, for me, you can without any issues store your credentials in the process.env. The only constraint is that you have to restart your server whenever you wan't to change password and you have to inject yourself the credentials in environement variables.
But if you're already have an sql database in your project, the best way is effectively to use a table User with hashed password. With this method you can change your password without restarting your app (but in your case is this really usefull ?) and if you're adding some users, the system will be already in place (but YAGNI)).