I made this wonderful dessert yesterday for company, and everyone loved it. Today I discovered the thread in early January and wanted to add my experience on the "creaming" question. I, too, wondered about how to "cream" -- to say I am not an experienced baker would be a major understatement -- and followed my wife's advice to use the food processor. The method is probably familiar (a stick of frozen butter cut into eighths and combined by pulsing with the sugar, next letting it run a bit until completely mixed, and then blending in the vanilla and the eggs by pulsing in the food processor). I then mixed in the flour and sugar with a wooden spoon in a mixing bowl. (I was warned not to use the processor at this stage as that would toughen the pastry.) Perhaps some will not approve of this approach, but the result was terrific.
I used very juicy, ripe Comice pears (three was all I could squeeze in)and took the advice of a previous Chowhound poster to glaze the tart with melted apricot jelly after taking it out of the oven. It all worked beautifully.
One question: since I would like to have the leftovers that others report inprove with time, can I add ingredients by a quarter or a half and use a larger pan?