In a large bowl, cream together butter, brown sugar and white sugar until fluffy. Beat in eggs one at a time then stir in the vanilla. Combine the flour, bicarb soda, salt and cinnamon; stir into the creamed mixture.
Mix in oats and nuts until just blended. Drop by heaping teaspoonfuls onto ungreased baking trays. Biscuits should be at least 5cm apart.
Bake for about 12 minutes in the preheated oven. Cool biscuits on a wire rack.