In a large bowl, cream together the brown sugar, white sugar and butter until smooth. Beat in the eggs one at a time, mixing well after each one. Stir in the vanilla, salt and bicarb soda until well blended, then mix in the ground pecans and flour. Stir in the chocolate chips last. Try not to over-mix once you add the flour.
Drop spoonfuls of biscuit dough onto ungreased baking trays so they are about 5cm apart.
Bake for 10 to 12 minutes in the preheated oven until the biscuits are just starting to brown at the edges. Let cool on the baking trays for a few minutes before removing to cool on wire racks.