The receipts

How I did it

The Economist prices a Big Mac in every country and calls the result an index. I did the same with a Big Mamma dinner. Four things that are on almost every menu in the group: the Mafaldine al Tartufo, a plain margherita, a Passion Spritz and the Tigramisù.

Two rules. In the UK and Germany the mafaldine is a sharing plate priced per person, so I take that per-person price. And the margherita is the plain Mammargherita where a menu has one; where the only margherita is the bufala version, I take that.

Prices come from the group's own menu site. If a city has several restaurants I use the median basket. Everything is converted to euros at the ECB rate of the day, dirhams through the dollar peg. Paris is 100. For pounds and dirhams the table also shows the exchange rate that would make the basket cost the same as in Paris, next to the real one.

Menus change with the seasons, VAT and tipping differ, and a city marked 2/4 or 3/4 is missing dishes and is compared with Paris on the ones it has. A city needs at least two of the four to be ranked. I never estimate a price: if a dish is not on the menu, it is left out.

The search box covers every priced item that turns up on menus in at least three cities, of them at the last count. Same spelling in different cases or with "Le nostre" in front is treated as one dish. They are there because they are fun to compare and never count towards the index.

Made by Emile Legendre, whose only connection to Big Mamma is eating there. Refreshed every Monday.