Cream butter until light and fluffy, then beat in heavy cream and vanilla.
Blend flour and 6 tablespoons of powdered sugar together and gradually add to the creamed mixture. Mix pecans in by hand.
Form the dough into one large ball, wrap it in plastic wrap and chill in the refrigerator for 1 hour.
Form dough into 18 small balls and place 2 inches apart on a greased cookie sheet. Using your thumb or the back of a rounded teaspoon, make a depression in the center for the frosting.
Bake at 325 degrees for 20 minutes. Remove to cookie rack and cool completely, about 45 minutes to one hour.
Frosting:
In a large bowl, combine cream cheese, powdered sugar, melted chocolate, vanilla, and 1 tablespoon of milk.
Beat with an electric mixer until fully blended and frosting has a creamy texture. If it is too thick, add additional milk 1 teaspoon at a time until it reaches desired consistency.
Using a dessert decorator with a flower tip, pipe the frosting onto the top of each cookie. If you don't have a dessert decorator you can use a spoon to dollop frosting on the top of each cookie.
Notes
You can double the recipe to make 3 dozen cookies if you likeTake the cream cheese out of the refrigerator when you put the cookies in the oven and it will be ready once the cookies have cooledMelt the chocolate in a microwave safe glass container in the microwave at 30 second intervals, stirring in between just until chocolate is melted