It depends on whether you’re referring to individual refried beans or the dish ‘refried beans’ as a whole.
If it’s the former, it would be ‘too many’ (individual) refried beans.
If it is the latter, it would be ‘too much’ (of) refried beans… Unless you had multiple servings, in which case it would be ‘too many’ (servings of) refried beans.
That is my opinion: as such it is subject to change should further information come to light.
An American Werewolf in London.
I stayed up watching it on my brother’s black and white TV. My parents had no idea. I nearly shit the bed afterward when my brother jumped on me in the dark and yelled “raaaah.”