Notes:
You can use pretty much any crisp, not-too-sweet, apple for this recipe. For the filling I like MacIntosh Apples for their intense flavor. I used unsweetened Granny Smith applesauce in the batter. If you use a sweetened applesauce your donuts will be much sweeter.
Mace is a relatively rare and sometimes expensive spice made from the outer coating of a nutmeg. You can substitute a pinch of ground cloves or just double up the nutmeg if you like.
If you don't have donut pans, you can make the fritters in a muffin tin