Butter and flour a 9 by 3-1/2-inch tube pan. Into a bowl sift together the tour, the baking powder, and the salt and in another bowl stir together the pecans, the cinnamon, and 4 teaspoons of the sugar. In a large bowl with an electric mixer cream the butter with the remaining 2 cups sugar until the mixture is light and fluffy and beat in the eggs, 1 at a time, beating well after each addition. Beat in the sour cream and the vanilla and fold in the flour mixture until the batter is just combined. Pour one third of the batter into the prepared pan, sprinkle it with three fourths of the pecan mixture, and spoon in the remaining batter. Sprinkle the remaining pecan mixture over the batter and bake the cake in the middle of a preheated 350° F. oven for 1 hour, or until a tester comes out clean. Let the cake cool in the pan on a rack for 15 minutes and turn it out onto the rack. bake 67