Laughing!
My DML always had to have Green Giant peas when she visited. Said she could tell the difference! So at the first meal I served them, kept the empty can under the sink, 2 weeks later when we had peas again they were the store brand. I hid that can, put the old can on the counter. When I asked if the peas were OK, she said yes, she could always tell Green Giant. My husband nearly choked trying not to laugh.