Preheat your oven to 350°F. Grease and flour a 9x5-inch loaf pan or line it with parchment paper for easy removal.
Mix the batter: In a large mixing bowl, whisk together using an electric hand mixer the cake mix, lemon pudding mix, eggs, sour cream, melted butter, oil, milk, lemon juice, and lemon zest, until well combined. The batter will be thick and luscious!
Bake: Pour the batter into your prepared loaf pan. Bake for 45–55 minutes, or until a toothpick inserted in the center comes out clean. (Mine was perfect at 50 minutes) If the top is browning too quickly, cover loosely with foil for the last 10–15 minutes.
Cool: Let the loaf cool in the pan for 10 minutes, then carefully transfer to a wire rack to cool completely.
Glaze it up: Whisk the powdered sugar, lemon juice and lemon zest until smooth. Drizzle over the cooled loaf and let it set for at least 15 minutes before slicing and enjoying!