Can streusel topping (nuts, butter, flour, brown sugar) be made in advance? Assuming it's wrapped and refrigerated, how far ahead? Thanks!

AJ, you could also put about a tablespoon of cornstarch in a clean coffee filter, tie it really well and put the bundle in the package with the streusel. Any moisture that accumulates will gravitate to the cornstarch first.

Thanks so much! This does indeed help. I'll put it in the freezer, for sure. The reason I ask this is that I made a streusel topping for the apple tart I baked at pierino's house for the party there last month. I had to drive 3.5 hours to get there, and did not put the topping into an insulated bag. By the time I actually got the streusel onto the tart (in that hot kitchen, where it was sitting out), it had turned into a sandy batter-like substance. (It still tasted great when cooked, however. But it just didn't have the usual attributes of streusel.) The butter had started to melt, I guess. I wasn't sure if the moisture absorption could be avoided, but obviously, it can! Thanks again. ;o)

For sure, AJ! I do that all the time -- prep topping, freeze it, and it's ready to go when you want to toss together a streusel, crispy or crumble. It can happily hang in the freezer for two weeks or so. Hope that helps.

For sure, AJ! I do that all the time -- prep topping, freeze it, and it's ready to go when you want to toss together a streusel, crispy or crumble. It can happily hang in the freezer for two weeks or so. Hope that helps.