Flavoring Crumbs

I add finely chopped toasted nuts to crumb toppings sometimes along with spices and a pinch of salt.

I bet tossing them with some lemon or orange zest and then letting it sit for awhile would work nicely, perhaps with a grating or two of fresh nutmeg. ;o)

I was actually just looking through the Milkbar book for some advice hah

Something similar, I want to make the milk crumbs from Christine Tosi's Milkbar book. And I want to flavor it with freeze-dried strawberry powder.

http://www.bonappetit.com/recipes/2010/09/milk_crumbs

I happily add spices to a crumb topping - cinnamon etc. to complement the flavours, but I think adding berries might make hings a bit soggy - I'd probably put the berries in the cake, and a bit of spice in the topping. I guess if you had some freeze dried berries or something that might work?