My friend brought me little Taiwanese cookies that taste like they contain tahini. Does anybody know a recipe?

Question

They are small about an inch long, square shaped and they have black powder inside just like poppy seed paste.

Answer 1

Sounds like black sesame cookies.  I don't know about a recipe, but you might be able to find it at an Asian grocery store, such as Ranch 99 if you live in the California Bay area.

Answer 2

Based on your description, it sounds like they are black sesame cookies.