In a large bowl, cream together the butter and brown sugar until smooth. Beat in the eggs one at a time then stir in the vanilla.
Combine the flour, bicarb soda and salt; stir into the creamed mixture. Mix in the oats, chocolate chips and chopped pecans. Drop by tablespoonfuls onto ungreased baking trays. Biscuits should be at least 5cm apart.
Bake for 8 to 10 minutes in the preheated oven. Allow biscuits to cool on baking tray for 5 minutes before removing to a wire rack to cool completely.