Mix the cake mix, pudding, oil, milk, sour cream and eggs for a couple minutes with an electric mixer.
Pour half of the batter in the bottom of a greased 6 quart slow cooker.
In a small bowl, combine the sugar, pecans and cinnamon.
Sprinkle half of the sugar mixture over the cake mixture in the crock pot.
Add the rest of the batter and sprinkle with remaining sugar.
Cook on low for 3-4 hours or until toothpick comes out clean.
In a medium size bowl, mix the icing ingredients until blended.
Drizzle over the coffee cake.
You may need to put some paper towels under the crock pot lid to soak up the extra moisture.
You can add or subtract the amount of powdered sugar to get the desired consistency of frosting you like.