I apologize in advance for how long this is, but it is a true story.
I had a a BRAT rescued boy who lied deliberately. He was a nervous, extremely picky eater and to get him to eat dinner (usually a high quality dry with half a can of moist mixed in) we would bribe him with ice cream.
Every day went like this: We'd put down his food, and he'd refuse it. We'd point at it and say 'Dinner!' and he'd shake his entire front half 'No!' - We'd say 'First dinner, Then TREAT' - you know how they understand phrases, this boy really got 'first X then Y' - so he'd reluctantly turn and enter the kitchen.
From the next room, we'd hear kibble moving around in the bowl and he'd come bouncing back in. We'd say 'Show me' and he'd turn around and run into the kitchen with us following him. The bowl would be mostly empty and we'd tell him how wonderful he was and reward him with a tablespoonful of vanilla ice cream.
You know how ritualistic basenjis are, this went on for a while. Then one day, when I was cleaning the kitchen floor, I moved the heavy wooden kitchen Island away from the bar it backed up to. Behind it were piles of rotting dog kibble.
I kid you not - Florian had scooped the detested dog food out of his bowl, and hid it. Then deliberately come get us to reward him. I have to admit, I was and still am really proud of him for out-smarting me.