Preheat oven to 350 degrees F. Grease & flour a bundt pan, 12 C fluted tube pan or 10" tube pan. In a large bowl, combine sugar & butter; beat until light & fluffy. Add eggs, 1 at a time, beating well after each addition. Gradually add 2 C confectioners's sugar; blend well. Add pudding (dry); mix well. By hand, stir in flour, cocoa & walnuts until well blended. Spoon batter into pan; spread evenly.
2Bake 45 - 50 minutes or until top is set & edges are beginning to pull away from pan (see note). Cool upright in pan on rack 1 1/2 hours. Invert onto serving plate; cool at least another 2 hours.
In a small bowl, combine all glaze ingredients, adding enough milk for desired consistency. Spoon over top of cake, allowing some to run down the sides & middle. Store tightly covered.
Nuts are essential for the success of this recipe!!!!!!
Since this cake has a soft filling...an ordinary doneness test can't be preformed. Accurate oven temps & baking times are essential.