At its most basic, the butter tart is a pastry filled with brown sugar, butter and egg. Oven alchemy transforms those simple ingredients into something spectacular. Inventive cooks have gone further with chocolate chips, coconut, nuts and other add-ins.
Unlike the Nanaimo bar — a midcentury British Columbian creation made with processed ingredients like custard powder and graham crackers — the butter tart goes back at least to the 19th century.
Mary F. Williamson, a retired fine arts librarian at York University in Toronto, traced the earliest mention to 1900 and the “Royal Victoria Cook Book,” published to raise money for the Royal Victoria Hospital in Barrie, Ontario. Margaret MacLeod’s recipe for “Filling for Tarts” (like some of the other community cookbook contributors, she was identified by her husband’s name, Mrs. Malcolm MacLeod) called for one cup of sugar, a half-cup butter, two eggs and a cup of currants.
There are as many theories about the origins of the tart as there are variations. The brown sugar pie, the Scottish border tart, Bakewell tarts and the Quebec sugar pie — each has been named a predecessor to the Canadian tart.
“Each of those things is their very own particular thing, very similar to each other, but they’re not all the same,” Ms. Driver said.
The very first butter tart recipe may never be found, because until recently cookbooks were not seen as items worth preserving.
“Most of these things were developed by housewives, and it wasn’t deemed important,” said Lenore Newman, the author of “Speaking in Cod Tongues: A Canadian Culinary Journey.” “Now that we’re actually interested in it, we go back, and we find there are a lot of holes in this knowledge. I…