Preheat the oven to 350 degrees F. Line a baking sheet with parchment paper and set aside.
In a medium mixing bowl, whisk together the almond flour, finely diced pecans, salt and baking powder and set aside.
In a small mixing bowl, whisk together the almond butter and maple syrup until smooth.
Pour the wet ingredients over the dry and stir thoroughly to combine.
Taking about 1 tbsp of dough at a time, press it into a ball shape (rolling it might cause it to fall apart) and place on the baking sheet. Using two fingers, gently press down on the dough to flatten it out a bit. Then with your thumb or the back of a 1/4 tsp measuring spoon (its the perfect size), press down in the center to make a small indentation. Repeat with all the remaining dough.
Bake 6-8 minutes, until they edges start to turn brown. They will still be delicate when they come out, but they will continue to firm up as they cool. If the indentations rose up a bit, you can gently press them back down with your thumb or the measuring spoon (I recommend the measuring spoon at this point since the cookies will be hot and I don't want you to burn your thumb!)
Let cool on the baking sheet for 1-2 minutes before transferring to a wire rack to continue cooling completely.
Once cool, fill the indentations with the icing of your choice.