Whats a common household ingredient/food that you have overlooked your entire life, until one day you realized it was delicious and versatile in ways you never saw?

I recently realized just how great tartar sauce is. I mean, I make mayonnaise-based sauces all the time, for fries, sandwiches, tacos, rice bowls, etc. Turns out that tartar sauce is basically just that, and can be used in so many dishes. I love it, and now I can't live without it.