Chop onion and using kitchen scissors, dice the bacon. Sauté in butter for 2 minutes in a non-stick pan. Add the cheese, SIDS HOT WORCESTER SAUCE, SIDS WINE & PEPPER MUSTARD, flour and SIDS SALT & PEPPER into a saucepan. Mix well and then add Guiness to moisten. Do not make it too wet!
Stir over a gentle heat until all is melted and when it is a thickish paste, remove from the heat, stop stirring and swerl it around the saucepan to cool, which it will do quite easily.
Leave to cool a little and meanwhile, toast the bread on one side only. Spread the rarebit over the untoasted side and brown under a hot grill.
This mixture can be made and kept in the refrigerator for several days if required. Sweet white wine can be used instead of beer and gives a good flavour.
Hint: Add an egg on top makes it a 'Buck Rabbit' or blended with tomato (or tomato soup) makes it a 'Blushing Bunny'.
History: - The notion that toasted cheese was a favourite dish irresistible to the Welsh has existed since the Middle Ages. In A C Merrie Talys (100 Merry Tales), a printed book of jokes of 1526 AD (of which William Shakespeare made some use), it is told that God became weary of all the Welshmen in heaven, "which with their krakynge and babelynge trobelyd all the others" and asked the Porter of Heaven Gate, St Peter, to do something about it. So St Peter went outside the gates and called in a loud voice "Cause bobe, yt is as moche to say as rostyd chese": at which all the Welshmen ran out and when St Peter saw they were all outside, he went in and locked the gates, which is why there are no Welshmen in heaven. The 1526 compiler says he found this story "Wryten amonge olde gestys".