It's kind of: I wonder... I wonder what I/we will eat today...

Also see http://www.guidetojapanese.org/learn/grammar/adverbs http://www.guidetojapanese.org/learn/grammar/sentence_ending for more sentence ending particles ("gobi"). か just indicates a (rhetorical) question, informal style. One important feature is that those particles differ for male and female speakers.

Hey :) かな is used when you are wondering about something. "What about..." "I wonder if..." "What if..." Cheers!