Thanks for your ideas on making HP sauce, i look forward to trying it out and will let you know how it tastes!!
As for the name HP, i always thought it stood for Houses of Parliament because there is a picture of Westminster on the bottle which is part of parliament, then i found this information that mentions Harry Palmer and Houses of Parliament but the latter seems more likely.
The original recipe for HP Sauce was invented and developed by Frederick Gibson Garton, a grocer from
Nottingham. He registered the name H.P. Sauce in 1896. Garton called the sauce HP because he had heard that a restaurant in the
Houses of Parliament had begun serving it (indeed, bottle labels today carry a picture of the Palace of Westminster). Garton sold the recipe and HP brand for the sum of £150 and the settlement of some unpaid bills to Edwin Samson Moore. Moore, the founder of the Midlands Vinegar Company (the forerunner of
HP Foods) subsequently launched HP Sauce in 1903.
Some stories suggest that the name HP was derived from the name Harry Palmer. Palmer was said to have invented the recipe and sold the product as "Harry Palmer's Famous Epsom Sauce". The story then goes that Palmer, an avid gambler at the
Epsom races, was forced to sell the recipe (to cover his debts) to F.G. Garton, a grocer from
Nottingham. However, there is no evidence in the official history of the brand to show Palmer existed, or had any claim to the development of the recipe. It also seems unlikely that Garton, a grocer from the Midlands would have come in contact with a gambler from the South of England.