Preheat the oven to 350F (180C) or 325F (170C) on a convection oven.
Line cookie sheets with parchment paper or silicone baking mats.
In a large bowl, beat together the butter and sugar until combined.
Mix in the vanilla, almond extract and salt.
Add in 2 1/4 cup all-purpose flour and 1 cup almond flour. Start with the mixer on a low speed and gradually increase until you no longer see pieces of flour. It should be a bit difficult to incorporate all of the dry ingredients.
Turn off the mixer. Take a section of dough and squeeze it in your hand. If the dough sticks together, it is finished. If it just crumbles and doesn't stick together, mix in 1-2 tablespoons of milk (do this slowly) until it sticks together. If when you squeeze the dough you end up with sticky dough attached to your hands, mix in a little more flour 1 tablespoon at a time.
Pinch of sections of dough with about 1 to 1.5 tablespoons of dough each. Roll into a ball and then pinch into a crescent shape.
Place crescents about 1.5 inches (3 cm) apart on the lined baking sheets.
Bake 1 sheet at a time in the preheated oven for about 12-14 minutes or until the tops no longer look doughy. Do not bake these cookies until they are golden brown.
Allow the cookies to cool on the cookie sheets for about 5-10 minutes. Then dust with powdered sugar by sprinkling 1-2 tablespoons at a time through a metal sifter.