What is the most underrated spice?

What spice packs a punch but doesn't get the spotlight? What is that secret something you love to sprinkle in when you're cooking? It could be something obscure and uncommon or a novel way you use something well known. Curious to see what spices people are in love with!

For me, it's dry mango powder. It is sour, tangy, tart. I add it sometimes to savoury things to give a kick of flavour. It has elevated my grilled cheese game like nothing else!