How would you handle this?

echowysp2

My 2 1/2 year old dd has been giving me some trouble with breakfast.  She usually is up before her brother and immediately wants breakfast.  She requests what she wants, usually oatmeal.  Problem is, once her brother is up a few minutes later, so will suddenly want what he's having and refuse to eat what I had made her and cry for quite a while.

I've tried to avoid this problem by trying to get her to wait until he wakes up because I know she's going to want what he's having, but she cries and wants food.  

I am sick of wasting food and refused to make her the toast she wanted after I made her the oatmeal she originally requested.  She cried for a while and finally is sitting to eat the oatmeal. 

My question is: is that too harsh for a 2 year old?   She's kind of young to understand about wasting food, but still, it's a shame to waste food.