It's a bit of trial-and-error since each hedgie is different. I use a small kitchen scale to weigh out how much food the hedgies are getting each night.
For Bella (an 376g adult), I measure out 10g.
Satin (a 680g adult), I measured out 9g.
Tex (360-380g adult), 12g.
Marlee (252-342g baby), 20g.
They each eat most of what I put out and leave a few grams in their dishes by morning. If, ever, they ate the whole thing, then I put a few more grams in their dishes when I spot them empty in the morning and then make sure to add a couple extra grams the next night.
In short, try maybe 20g worth when hedgie comes home, if your hedgie eats all of it, put more in the dish in the morning and increase the 20 to maybe 22 or 25g at night. If hedgie doesn't eat all of it, I'd still put around 20g out a few more nights in a row -- they can be anxious/upset/scared at first and take some time to settle in and don't always eat their normal amount the first few nights. Then take it from there... if there's always a lot left, then decrease the g's; if it's all gone, increase the g's.
You'll want to be able to put out fresh kibbles each night, so I wouldn't advise filling up a big bowl and just letting it sit a few days until hedgie's eaten all the way through.