This recipe from Jill Dupleix, for Tahini and Date Brownies, made a fantastic chocolate cake, but I couldn't really relate it to the sort of thing I expect from a brownie recipe - it was far too light! Using puréed dates gave a lovely soft, but rich, texture, as well as cutting down on the amount of refined sugar and fat usually used in a recipe of this size, but did stop the brownies being dense and fudgy.
The amount of tahini in the recipe didn't make much of an impact on the flavour either. It's hard to tell unless I made the same recipe without the tahini, but we certainly didn't bite into a brownie and say 'Oooh! Good sesame flavour there!'
If you are worried about the amount of refined sugar your family is eating, you would probably enjoy this recipe. I think it would make a good rich chocolate layer cake too - I'm pretty sure it would fit into 2 x 18cm (7") sandwich tins.