The original directions say to put the rice mixture in a shallow baking dish and a cookie sheet with sides is too shallow(makes rice dry and leathery.
I'm not sure how much cut up chicken you could fit, as I remember it making everything come up too close to the edge of the pan, so don't crowd (It's why I do legs).
You need enough room for the rice to expand.
These are the only issues I've encountered.
It amazes me at how delicious this dish is and usually skeptical on too easy.
Spray a 13x9" glass dish with Pam cooking
Note: I rinse the rice well in a strainer first.
and sprinkle with dry soup mix.
Tip: The steam will condense and drip down
the sides if you don't crimp and you'll just have
a mess. You need all that moisture for the rice anyway.