The elusive butter tart

Butter tarts are a famous Canadian dessert.  Famous for a reason - they are very very tasty.  And being that my mother was Canadian, we had these treats often while I was growing up.  And when I moved out and began baking on my own, I used my mother's recipe.

You can see it's well-used.  In the upper right corner, covered by a stain, is the word 'Viola.'  Viola was my mother's sister, so presumably it came from her.

One summer while visiting relatives near London Ontario, I went looking through my Aunt Betty's (my mom's other sister) cookbook, and found another recipe for butter tarts.  It was similar, but slightly different.  My Aunt Betty was used to feeding a crowd (she and Uncle Art ran an RV resort), but even reducing Aunt Betty's recipe by a factor of 8, there are still differences.

And shortly after that summer trip, my mother gave me her mother's recipe box.  Inside was a hand-typed card, with somewhat vague instructions for making the tarts.  This one is apparently from my great aunt Helen, my grandmother's sister-in-law.

Even more differences.  Including a different name.  Cheese tarts?  Where exactly is the cheese?

Which one is the true family recipe?  Perhaps all of them?  Or perhaps none - my mother always said that Viola's tarts tasted better than hers, and suspected that Viola had left something out of the recipe she gave her.  (Perhaps it is the cheese?)

Maybe someday, when I have a lot of time and a lot of company coming over (two situations that will likely never coincide), I'll make all three recipes.  And see if anyone can taste a difference.