[mangoandmimi]

I mean you can work out exactly how many extras you need if you work out total mealworms needed then add them to the mix and store it all in a container. Either that or if you know how long she takes to get through a bag you can work out # of mealworms a day.
To be honest though you're probably only looking at about 2 mealworms a day give or take - don't know how old she is but that would probably do it if she's an adult. But as she gets over 1.5 years old you may want to reduce the number of them a bit to lower protein. So eventually maybe 1 a day to every few days would be fine. Like I said I haven't done the maths properly but an extra mealworm here or there isn't going to make a huge difference.

Oops I wrote that assuming you were going to feed a mix low in protein (15-16% say). If it’s something like Harry hamster you really won’t have to add much more protein as it’s already around the right level.
I do recommend changing the mix itself if you weren't already going to do that as tbh 10-12% protein is just too low to work with, you'd have to be adding a huge amount of animal protein which wouldn't be ideal.