Kellogg's - Crispix

Brocho before eating this: Take a Crispix and split it. Say Borei Minei Mezonos and eat the rice side [dark side], and then say Borei Pri Ha'adama and eat the corn side [light side].

Brocho after eating the proper shiur of this: Borei Nefashos

Source: Star-K Cereal List

Note: Halachically Speaking (volume 4, issue 2) says that the custom is to say Shehakol Niyeh Bedvoro