Always expect the unexpected

ALWAYS ASK restaurants, bakers, cooks, etc. if the food you're getting contains your allergen. This could seem odd, but trust me, sometimes foods include weird ingredients.
For example, I've encountered a bakery that used almond paste for ALL of its baked goods, including bread. Also, many restaurants use peanut and sesame oil to cook their foods (including burgers)! In other countries and in foreign foods (that are even sold in America) they use different names for the same foods. You need to make sure that you know the different names for your allergen. For example, my mom cooked a ravioli that had an ingredient called "pinoli" in its sauce that actually meant "pine nut," but my mom didn't know that and assumed it was fine. IF YOU DON'T KNOW IT, LOOK IT UP. Don't take the risk. It never hurts to ask!