I'm making them for my aunt who loves lemon and coconut. I'd like to top with toasted coconut. Would you put in on the topping immediately or wait until it's baked for some of the time?
I make coconut-lime bars which are essentially the same thing...this is what I do...
Bake, cool to room temp then chill 2 or more hours. Lift bars out of the pan, cut into bars, then sprinkle toasted coconut on top. That way, the coconut stays crunchy and you aren't forcing pieces between the bars when you cut them.