Beat butter at medium speed with an electric mixer until creamy; gradually add sugars, beating well. Add eggs, 1 at a time, and vanilla, beating until blended after each addition.
Combine flour, cocoa, and soda; add to butter mixture, beating at low speed until blended after each addition. Stir in 1/2 cup pecans. Shape 1 tablespoon dough around each candy piece, covering completely, to form balls.
Combine remaining 1/2 cup pecans and 1 tablespoon sugar. Gently press the top of each ball into pecan mixture. Place balls, pecan sides up, 2 inches apart on baking sheets.
Bake at 375° for 7 to 10 minutes. Cool on baking sheets 2 minutes. Remove from baking sheets; cool completely on wire racks.
Melt coating squares in a saucepan over low heat, stirring constantly until smooth. Drizzle over cookies.
NOTE: For testing purposes only, we used Twix Caramel Cookie Bars.