In her book "cakes" Barbara Maher has a recipe for sachertorte that she says comes from Frau Sacher herself. It's wonderful. Very easy. also one for dobostorte. The dobos is not made like a spongecake cut into layers, it;s made like baked pancakes (that is, a sponge batter, poured on the underside of cake pans, about 1/8 inch thick, baked quickly and removed - a bit complicated. My hungarian friend says her recipe as i made it is exactly the way she remembered it)/
I'm not near my cookbooks now, but you might look it up - maher did another book called "incredible cakes" or something like that, and the dobostorte in that one is not as good. The older book, without color illustrations, is just called "cakes".