Mom started making hot cross buns for Easter a long time ago. She had read an idea to put a marshmallow in the center of a bun (the marshmallow is first dipped in butter and then cinnamon sugar). The marshmallow leaves a sticky hollow in the center of the bun, representing, I believe, the empty tomb. She decided she could improve upon this candy center, and made several iterations, including almond paste. This is what she likes best, and I'm inclined to agree that it is perfectly wonderful (although I also liked those marshmallow ones, back in the day).
I think traditional hot cross buns have raisins and such-like in them. That's only because those people haven't discovered this yet.
Hot Cross Buns
1 recipe cardamom rolls (search on the blog)
you can replace some of the flour with some potato flour, perhaps 4T, ish. Put it in early.
mini semisweet chocolate chips
toffee bits
chopped pecans
Put 1 t each of chocolate chips, toffee, and pecans in the center of each roll.
When they are cool, pipe crosses on the buns with a simple frosting.