Preheat the oven to 350 F. Combine cake mix, sugar, melted butter, sour cream, eggs, and vanilla in a large bowl. Mix thoroughly. Spray non stick spray in bundt pan.
Spoon half of the batter into the pan. Mix together the sugar, cinnamon and chopped pecans in a different dish and sprinkle them on top of the batter (reserve 3-4 tablespoons of the nut mixture). Try not to let it touch the sides of the pan.
Spoon the remaining batter on top and smooth it out. Bake for 50-55 minutes or until a skewer comes out mostly clean with moist crumbs attached.
Then let the cake cool in the pan, on a cooling rack, for about 20 minutes. Then carefully flip the pan over with a wire rack or plate on top and slide out of pan to continue to cool.
In a large glass, whisk together all the ingredients for the glaze. It should be neither too thick nor too runny, and should be easy to spread on the cake. Pour the glaze over the top and sprinkle with the remaining nut mixture. Let the glaze set.