i've taken food with me on a plane several times. a sandwich or some type of snack. never brownies specifically. i don't think they'd care about brownies in your carry on, UNLESS they suspected it was weed...and a dog might still smell pot in pot brownies. i wouldn't recommend risking it. but i have taken pot with me on a plane with me no problems. lucky, but not smart the bud is probably all insanely good and expensive
as long as they are not in a special container like at Green Cross in SF then you should be fine just carrying it on with you. here is the green cross menu: http://www.thegreencross.org/ver3/
I've taken brownies on planes before and never had a problem. Put them in my carry on or laptop container with no issues. I guess if security spotted them I would just say its a snack and if they make you toss them its not a big loss. I don't think they would suspect anything unless they smelled really bad, mine usually don't. People take food on airplanes all the time that they buy after passing thru security. Or worse case stash them in your checked luggage, you will be ok
just throwing this out there, but i got busted for edibles, and it sucks. you dont get taken easy at all. i had a few hash oil lollipops and got hit with between 1oz but under 5lbs possession. so if you are going to take them through security, as a worst case scenario be prepared to take a hit for some high weight possession charges because though getting caught in the cali airport might not be that big of a deal besides having to travel back for court wherever you are going to is bound to have stricter punishments and you will have what is considered a lot of weight.