Chocolate Peanut Butter Cups (Gluten-Free)

So I know its gluten-free flours, but these are AMAZING.  Maybe I'll work on the regular flour alternative.  They are worth it even so.

1 C. + 2 1/2 T. brown rice flour
1/3 C. + 2 1/4 t. potato starch
2 T. + 2 3/4 t. tapioca flour
1 t. baking soda
1/2 t. baking powder
1/2 t. xanthan gum
1/2 t. salt
2/3 C. Dutch-process cocoa (I use regular, cause I'm cheap)
1/4 C. + 3 T. almond flour
6 T. butter, room temp.
1/2 C. vegetable shortening
1 C. sugar + extra for rolling
1 large egg
1 t. vanilla

Filling:
1 large egg white
3/4 C. creamy, unsalted peanut butter
3 T. butter, room temp.
3/4 t. vanilla
1/2 C. powdered sugar

In a medium bowl, sift dry ingredients together.  Set aside.  In large bowl of electric mixer, combine butter, shortening, and 1 C. sugar.  Set speed to high, beat until light and fluffy, about 2-3 minutes.  Add egg and vanilla and beat until light and fluffy, about 2-3 minutes.  Reduce mixer speed to low, add flour mixture, mixing until just incorporated.  Chill in covered bowl for 1-2 hours or overnight.

Preheat oven to 350.  Line cookie sheet with parchment, or spray with cooking spray.  Mix filling just before baking cookies.

Filling:  In the small bowl of an electric mixer, combine peanut butter, butter, and vanilla.  Set mixer speed to medium and beat until smooth.  Add egg white and beat until well incorporated.  Reduce mixer speed to low and mix in the powdered sugar.  Set aside.

Using a small cookie scoop, form the base cookie dough into 1-inch balls.  Roll the balls in granulated sugar.  Place the balls on prepared cookie sheets, spacing about 2 inches apart.  Make an indentation about 1/4-inch deep in the center of each ball.  Shape a level 1/2 t. of the peanut butter filling into a small ball and place it in the center of each cookie.  Gently push the edges of each indentation over the peanut butter ball until only the top of the ball is visible (I usually smash each cookie down just slightly at this point, but it's probably not neccessary.  I also eyeball my sizes, and get impatient, so by the last few I'm making monster cookies.)

Bake cookies until puffed and slightly cracked on top, about 10-12 minutes.  Cool on cookie sheet 1-2 minutes, then transfer cookies, still on parchment, to wire racks to cool completely.  Store in airtight container up to 3 days.  Makes 48-60 cookies.

Any leftover peanut butter filling can be baked into treats.  Roll leftover filling into 1 1/2" balls and bake until golden brown, 10-12 minutes.