Catsup or Ketchup?

The etymology of the word ketchup has multiple possibilities. We know that in the 17th century, the Chinese had a mixture of pickled fish and spices called (in the Amoy dialect) kôe-chiap or kê-chiap. This was far from the modern-day tomato based condiment we use, but similar in sound and use.

By the early 18th century, the Chinese table sauce had made it to the Malay states (present day Malaysia and Singapore). There, English explorers discovered it and the Indonesian-Malay word used for the sauce was kecap (pronounced "kay-chap"). It's not hard to see that evolving in English to "ketchup" spelling. American Colonists brought it with them to the New World. We find the word in the 1690 Dictionary of the Canting Crew.

The spelling of "catsup" in American English is considered "a failed attempt at Anglicization." Catsup is the dominant term in American English and Canadian English, and it is particularly prominent in some southern US states.

It was news to me that in some places catsup is considered to be tomato sauce that is used on pasta and not as the condiment.