DD2 is EBF but I want to use formula to mix her cereal since I prefer to save my EBM for bottles in the event that I'm not home with her. I don't know much about formula but does it make a difference if I use powder or premade formula in the cereal? Also, once the formula & cereal are mixed, is it ok to then microwave it for a few seconds to warm it or will that do something to the formula?