In a large bowl, combine the finely crushed Nilla Wafer cookies with the finely chopped pecans, 3/4 cup of powdered sugar and the cocoa powder. Stir the corn syrup into the bourbon until blended; add to the Nilla Wafer mixture.

Using a spatula, stir the mixture together until moistened and combined. Using a cookie scoop, scoop Tablespoon-sized balls of the mixture and roll them in your palms gently to smooth out. Place on a foil-lined baking sheet. Repeat with remaining balls.

Using the remaining 2/3 cup powdered sugar, coat each bourbon ball in powdered sugar. Chill for about 20-30 minutes or until set before serving. Can be stored in the fridge, covered, or at room temperature, covered.