HP Sauce is a brown sauce originally produced by HP Foods in the United Kingdom, now produced by the H. J. Heinz Company in the Netherlands. It was named after the Houses of Parliament. It was the best-selling brand of brown sauce in the UK in 2005, with 73.8% of the retail market. HP Sauce has a malt vinegar base, blended with tomato, dates, tamarind extract, sweetener and spices. It usually is used as a condiment with hot or cold savoury food, or as an ingredient in soups or stews.

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