Preheat the oven to 350°F.

In a large mixing bowl, sift together the all-purpose flour, cake flour, baking powder, and salt. Set aside.

In the bowl of a food processor or high-speed blender, combine the sugar and lemon zest. Pulse a few times to evenly distribute the zest. Add the lemon juice, eggs, and sour cream and pulse until combined. On low speed, gradually drizzle in the melted and cooled butter in a slow steady stream until well combined.

Make a well in the center of the dry ingredient mixture. Pour in the wet ingredients. Mix gently with a rubber spatula until just combined. Batter will be slightly thin.

Grease a 10 or 12-cup bundt pan generously with baker’s nonstick cooking spray, such as Baker’s Joy, or melted shortening. Use a pastry brush to spread the spray into every nook and cranny of the pan. Immediately pour in the batter.

Bake until a toothpick inserted into the center comes out clean or with just a few moist crumbs attached, about 50 to 60 minutes.

Cool in pan for 15 to 20 minutes, then run a thin flexible knife around the edges before inverting onto a wire rack. Cool completely.

In a small bowl, whisk together the glaze ingredients until thick but pourable. Add more juice or milk to thin out or more powdered sugar to thicken until your desired consistency. Spoon over the cake, letting it drip down the sides if desired. Let set for 15 minutes before slicing and serving.

The glazed cake can be covered in foil or plastic wrap and stored at room temperature for up to 2 days.