Grease bundt cake pan. Mix together chopped pecans, 3/4 cup sugar and ground cinnamon. Cover bottom and sides of the bunt pan with 1/4 of the above mixture.
Blend together in a large mixing bowl: cake mix, pudding mix, 4 eggs, sour cream, vegetable oil and vanilla. Alternate layers of batter and crumb mixture in the greased pan.
Bake in microwave oven 5 minutes on low. Turn pan around if not on turn table. Bake 12 minutes on high, turning pan 1/4 turn every 4 minutes. Cool 18 minutes before turning out onto a cake dish. Baking time may vary depending on the wattage of the oven. To test for doneness, press lightly on top of cake and if it springs back it is done. Sometimes the very top of the cake will remain moist, don't keep baking it until it is dry because the cake will be too done. Enjoy!