Preheat oven to 180 degrees C. Coat a ring tin with non-stick cooking spray and dust with bread crumbs. Sift together the flour, bicarb soda and salt. Set aside. In a small bowl, mix brown sugar, cinnamon and chopped pecans; set aside.
In a large bowl, cream together the butter and white sugar until light and fluffy. Beat in the eggs one at a time, then stir in the vanilla. Beat in the flour mixture alternately with the sour cream, mixing just until incorporated. Spoon half of the batter into prepared pan. Sprinkle half of the pecan mixture over the batter. Repeat with remaining batter and pecan mixture.
Bake in the preheated oven for 60 to 70 minutes, or until a skewer inserted into the centre of the cake comes out clean. Let cool in pan for 10 minutes, then turn out onto a wire rack and cool completely.
In a small bowl, combine icing sugar with milk, a tablespoon at a time, until desired consistency is achieved. Drizzle over the cake.