1 lb. creme-filled chocolate sandwich cookies (such as Oreo or Hydroz)
1/2 c. (1 stick) butter, melted
1/2 gal. vanilla ice cream, slightly softened
1 (8 oz.) container frozen non-dairy whipped topping, thawed
1 c. pecan halves or pieces
1 (16 oz.) can chocolate flavor syrup (such as Hershey's)