[Tax-chick]

As I understand it, “piezas” implies that the article should be in pieces, while “pedazos” or “pedacitos” suggests that would should be whole is in smithereens.

[SoothingDave]

Dos piezas de pollo con papas fritas, por favor.

[xsmommy]

that is correct.

[SAJ]

Ah, excellent. Mucha gracia, as they say here in Cocle province. The local dialect drops final 's's like crazy, and somehow mutates many 'd's into 'l's. This, of course, is just brutal for non-native speakers to understand.

My favourite (?!) is the common phrase 'mas o menos', which in Cocle becomes one portmanteau word, to wit, 'maomeno'. First time I figured it out, I LOLed. The Panameno gent was, shall we say, nonplussed.