Preheat oven to 300 degrees F.:
Prepare two baking sheets with parchment paper, or use silicone linings.:
Place the pine nuts in a bowl.:
In a food processor, break up the almond paste into small pieces, and pulse with the two sugars and the flour.
Once the mixture is finely ground, begin to add the egg whites a little at a time, just until the dough comes together.:
Depending on the humidity, or the size of your egg whites, sometimes you may need all of the egg whites, while other times you won't.
Using a spoon and slightly wet hands, scoop a small spoonful of the dough, and place this into the bowl of pignoli.
Roll the cookie arround until it is lightly coated, and then place it on the prepared baking sheet.
Continue forming the cookies in this manner, placing them 2 inches apart on the baking pan.
Bake the cookies 20 to 25 minutes, and then cool.
Dust lightly with powdered sugar before serving.: