This one’s used to say that someone (or something!) is fully formed, full-blown, or legit.
It’s often used by abuelas to say that someone’s now a fully-grown adult, for example.
You can think of it like:
👉 full-blown / fully-fledged / legit
🌪️ When to whip it out
Whenever you want to say that someone’s fully formed or complete:
Ya es un abogado hecho y derecho.
He’s a fully-fledged lawyer now
Ya no es un chavito. Es un hombre hecho y derecho.