Will I never find the raisin croissant of my dreams?

Mike, the correct name is Pain aux Raisins, btw, just as what is sold here as a chocolate croissant is a Pain au Chocolat.

Croissant being French for crescent, you see and being more indicative of the shape. The only filled croissant is the Croissant aux Amandes which is crescent shaped with almond paste and slivered almonds. Most of the other breakfast pastries, though not all, are considered filled breads and called Pain (the Palmier being the other exception that comes to mind).

Are you certain it really is a custard filling, though? My impression in 30+ years of visiting Boulangeries was more that it was a trick of the dough somehow resulting in a a very soft, almost mushy consistency in the center (custard sounds more appetizing, though it is tasty). But I admit Pain aux raisins is not my favorite, so I could certainly be wrong. The point is that adding custard may, in fact, have been a non-traditional tarting up of the pastry so you are looking for someone else who cheats the same way. (Be careful if you find them )

I do love a good Boulangerie.

It has been a while, but the Swissotel on Wacker used to offer decent pastries, inclduing Pain aux Raisins - there was a stand in the basement concourse where one could buy them to go.

There is some sort of Jesuit outpost in the near west suburbs whose sisters like to bake and have taken to selling their products in the Lisle Farmer's market on Saturday mornings this year. They make good bread, pastries and excellent fruit tarts both in single serving and full sizes. I have not seen a Pain aux raisins there, but I will ask them when next I stop by, which should be next week. Sorry to be vague about the place, but the labels they use contain nothing more than a 708 phone number and I have not paid enough attention to the name when visitng with them.