You'd have to declare for for sure. If you can keep the cooked food vegetarian, it'll make your life easier. Otherwise, find out if beef importation is (still) currently banned or not. Even if not, the trouble is the U.S. Dept. of Agriculture may question whether it's Canadian origin or not (if they care about that). Best is to use a meat that's easily identifiable and distinguishable from something prohibited such as chicken/poultry.