**The safest choice is to discard it.** [Mrs. Richardson’s says to refrigerate its sauces after opening](https://mrsrichardsons.com/about/faqs/), and I couldn’t find manufacturer guidance confirming that an opened jar is safe after sitting out overnight.

That doesn’t prove it spoiled, but a normal smell or appearance can’t establish safety—so don’t taste it to check. [USDA food-safety guidance](https://www.fsis.usda.gov/food-safety/safe-food-handling-and-preparation/food-safety-basics/refrigeration) explains that unsafe food can still look fine.