Nutella Buttons will also be good filled with marmelade.
I used lemon marmelade I had left over and black butter, a typical apple-spice-spread from the Channel Island. For the decoration I went with Dorie's recommendation and used white chocolate.
The lemon-chocolate-combo is great! I had no taste of the ones I made with black butter. But I am pretty sure they are as great as the others!
I can imagine them very well with nutella or chocolate, but I guess any spread is fine. I used mini-muffin-tins (mine hold about 2 teaspoons of batter). Next time I would use even smaller ones - just fot the looks. I think they would be even prettier as "one-biters" :-)
For the recipe, have a look at Dorie's great book at p 188, and don't forget to stop by the groups page to see what the rest of us made out of this recipe!