Thumbprint Cookies with Ganache

I made these yesterday for The Blog Tech and his Fiance.  They love cookies and she had never had these before.  This is my mom's recipe and I have made them for years and years.  My mother did not make ganache, that is my addition.

 Ganache is very easy to make.  Just bring 1 cup of cream to a low boil and pour it over 16 oz. of good chocolate. I used a 71% dark chocolate.  Let it sit for about 10 minutes.

 Whisk to incorporate the cream and you end up with a silky, smooth ganache.  Set it aside.

 Cream 1 C. of butter with 1 C. of confectioners sugar and 2 tsp. of vanilla extract.  Separate 2 eggs and set the whites aside.  Add the yolks to the butter mixture.  Gradually beat in 2-1/2 cups of flour and 1/2 tsp. of salt.

 Whisk the egg whites with 1 T. of water.  Form the dough into walnut sized balls, dip each in the egg whites and roll in finely chopped walnuts.

 Place them on a parchment covered cookie sheet and press in the center of each ball.  I use the end of a wooden spoon to do this.  Bake them in a 350 degree oven for 15-18 minutes.  The bottoms should just be turning golden.

 Remove them from the oven and indent them again.

 Place a dollop of ganache in each indentation. Let them sit for about an hour or so to set up.