[3] The name is first attested in the 19th century, and is a corruption of the term en surprise, which is used in French cuisine for all types of croquettes or pieces of meat covered with breadcrumbs.

[4] Originally, they were filled with chicken giblets, mincemeat or provatura (a type of cheese from Lazio),[1] now also with a piece of mozzarella; the whole morsel is soaked in egg, coated with breadcrumbs and then fried (usually deep fried).

They are usually eaten with the fingers: when one is broken in two pieces, mozzarella is drawn out in a string somewhat resembling the cord connecting a telephone handset to the hook.

Now they are commonly served in most pizzerias all around Italy as an antipasto.

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