1. Preheat the oven to 350F. Spray or grease a Vida by PADERNO Non-Stick Bundt Cake Pan, 9.5-in.
2. Combine the flour, baking powder, baking soda and salt in a small bowl. Reserve.
3. Take the zest off the lemon using a vegetable peeler. Try to get as little of the white pith as possible. Combine the zest with 1 cup of the sugar in a blender. Puree until combined.
4. Mix the butter, lemon-sugar and remaining sugar in a large bowl, using an electric mixer on medium speed, until fluffy. (You can also do this by hand). Add the eggs and mix vigorously until well-combined. Stir in the vanilla.
5. Add the flour mixture and stir until barely combined. Add the sour cream and lemon juice and stir very gently until combined. Spoon this batter in the prepared bundt pan.
6. Bake for 50 - 60 minutes or until a cake tester inserted into the centre of the cake comes out clean. Let cool in the pan on a rack for 10 minutes, then flip onto a rack to cool another 10 minutes.
7. To make the glaze, whisk together the icing sugar and 2 tablespoons of lemon juice or milk in a small bowl. Add another tablespoon of liquid only if the glaze isn’t at all runny. After the cake has cooled on the rack for 10 minutes, spoon the glaze all over the cake, letting it drip down the sides. Cool completely.
Make Ahead: This cake freezes well. Wrap fully-cooled cake in 2 layers of plastic wrap and tuck into a zip-lock bag. Freeze for up to 1 month.