Six things you didn't know about hot cross buns

• How to make hot cross buns

The hot cross bun is one of the British Commonwealth's most loved and literal foods. They're buns. With a cross. And, heaven forbid, they should not be served piping hot from the oven. Here are six bits of trivia in advance of Good Friday when the smell of warm spice fills kitchens throughout the country.

Burial buns

A decree was issued in 1592 by "The London Clerk of the Markets" that forbid the sale of spiced buns except at burials, Christmas and Good Friday. Given that hot cross buns seem to be on the shelves from New Year's Day onwards in Australia, I think it's safe to say that rule is no longer enforced.

Two for one?

"Hot cross buns! Hot cross buns! One a penny, two a penny. Hot cross buns." The nursery rhyme so many children first learn on the recorder dates back to the 18th century and was probably based on the spruiking calls of London bun-hawkers. Why would you want to buy one bun for a penny when you can get two for the same low, low price? Because small buns were sold as a pair while the the bigger guys were traded individually.

Mouldy superstition

According to the The Oxford Companion to Food, old English superstition dictates that hot cross buns and loaves baked on Good Friday were impervious to mould and would be kept as lucky charms from one year to the next. Delicious stuff.

Kilojoule counting

A standard, 27 per cent fruit hot cross bun from Coles contains 1102 kilojoules. This is only slightly less than a McDonald's cheeseburger, which has 1180 kilojoules (along with a much higher fat content but lower sugar). It would take an 80-kilogram person about half an hour of jogging to burn off one bun, however, that's provided you eat the bun without butter.

Before there were gluten-free varieties …

The earliest hot cross buns might date back to ancient Roman times. When archaeologists excavated the city of Herculaneum, which suffered from the same fiery fate as Pompeii, two carbonised loaves were found in the ruins, each marked with a cross. The cross was probably to make the bun easier to break into four.

Old bun

The world's oldest hot cross bun could be more than 200. According to the BBC, a couple from Essex, England, possess a bun with an accompanying letter stating it was produced in Colchester for Good Friday in 1807. The bun looks to be in reasonably good nick, although might need a few seconds in the microwave for morning tea at Essex Rotary Club.