In a large bowl, use an electric mixer and beat together the cake mix, eggs, oil, dry pudding mix, and soda (or water) for about 3 to 4 minutes. Stir in the poppy seeds.
Spoon batter into pan.
Bake at 350 degrees for 30 to 35 minutes or until a toothpick inserted into the cake comes out clean.
For the optional glaze. Place powdered sugar in a medium size bowl. First add just 2 tablespoons of the fresh lemon juice. Whisk together. Add a bit more lemon juice if needed to get the right consistency to drizzle over the top. You don't want it too thick or two thin. Top cooled caked with glaze, if desired. To pump up the lemon flavor in the glaze you can also add some fresh lemon zest to the powdered sugar before juicing the lemon.
Notes
Don't have a bundt pan? You can also use 2 – 8 inch loaf pans or 4 to 5 mini loaf pans or muffin tins to make lemon poppy seed bread or muffins.
If you are not making the glaze, it looks pretty with a dusting of powdered sugar over the top.