Preheat oven to 300 degrees. Get eggs, margerine and milk to room temperature. (Set eggs in warm water for 10-15 minutes; microwave milk and margerine. Margerine should be soft -- NOT MELTED). Add salt and baking powder to flour. Using the mixer, cream together sugar and softened margerine in a large mixing bowl. When creamy, add 1 egg at a time and mix well. Add flour mixture and milk, alternating between the two until gone. When mixed well, add vanilla and mix again.
Using Baker's Joy, spray bundt pan. Pour batter into pan and bake at 300 degrees for 1 hour and 10 minutes to start. At the end of that time, raise oven temperature to 325 and continue baking for an additional 10 minutes.
Remove from oven. Set pan on baking rack or pot holders to cool completely. Place a plate on top and invert to allow cake to ease out of pan. If it sticks a little, take a plastic knife and slide under the top of the cake, down the sides and middle to help to release. If you like, sprinkle Confectioner's sugar on top or eat it plain.