n. — Food, Prairies, especially Saskatchewan and Manitoba
cookie, pastry or cake better than the everyday fare; usually in the plural, dainties.
Type: 5. Frequency — In the international context, dainties is used quite widely, see Chart 1. Its widespread dissemination in the English-speaking countries (see Chart 1) stems from its English roots, going back into the 14th century.
In the Canadian context, the term has special relevance as a regional term in Saskatchewan and Manitoba, which renders dainty a Prairie regionalism on the grounds of frequency (see Chart 2, see the 1999 quotation). The term is a semantic specialization of the meaning 'anything pleasing or delicious to the palate; a choice viand, a delicacy' (OED-3, s.v. "dainty" n. (6)). Various semantic connections can be made to the OED-3 meaning, such as cookies for social gatherings, as on the Canadian prairies, or of more refined quality, for instance.
See also COD-2, which marks the term as "Cdn (Prairies & NW Ont.)".
See also: Nanaimo bar
Images:

Chart 1: Internet Domain Search, 7 Sep. 2015 
Chart 2: Regional Domain Search, 7 Sep. 2015