What do sex and food have in common?
Grandma makes both better.
What do sex and food have in common?
Grandma makes both better.
Listen, you wouldn't know anything about grandmas, would you? Okay, sex and food are different things, right? But the joke is that people often think their grandma's cooking is the best, and the joke suggests that grandma is also good at sex. It's unexpected and kinda cheeky.