Pre-heat oven to 350°F.
In a large bowl, mix all the dry ingredients (powdered almonds through sugar).
Add the butter cubes, and massage them into the dry ingredients with your hands until you can no longer discern them; the mixture should look crumbly/sandy.
Add all remaining ingredients (EXCEPT powdered sugar), mixing with a wooden spoon until they are completely incorporated, but do not over-mix.
Divide the dough into 2 balls; it will be sticky but use a bit of additional flour to work.
One at a time, lay each ball on a well-floured surface; sprinkle the top with flour, then flatten with your (well-floured) hands into a circle about 8 to 10 inches and 1 to 2 inches thick.
Cut each circle into 8 wedges and place on a non-stick bake sheet (use a spatula if needed to facilitate the transfer).
Bake for 12 to 15 minutes, until the scones are puffed and golden in color.
If desired, dust with powdered sugar when cooled.
