Puerto Rican Tupperware
An empty tub initially meant for butter that is used to hold a number of delicacies from Puerto Rico, including, but not limited to: arroz, habichuelas, arroz y habicuelas, arroz con pollo, sofrito, asopao, sancocho, and much more. Can often cause trust issues in children, due to the confusion of whether or not a butter tub will actually have butter in it. May also be found in Cuban and Dominican households.
I wasn't paying attention when I opened the Puerto Rican tupperware in my mom's fridge and now I have arroz con gandules all over my toast.