1. Preheat the Oven: Preheat your oven to 325°F (163°C). Grease and flour a 10-inch Bundt pan, ensuring all crevices are coated to prevent sticking.
2. Prepare the Cake Batter: In a large mixing bowl, cream the softened butter and granulated sugar together until light and fluffy, about 3-5 minutes. Add the eggs one at a time, beating well after each addition.
3. Incorporate Dry Ingredients: Gradually add the all-purpose flour to the butter mixture, mixing until just combined. Do not overmix.
4. Add Flavorings: Stir in the lemon zest and vanilla extract until evenly distributed.
5. Incorporate 7 Up: Gradually add the 7 Up to the batter, mixing on low speed until the batter is smooth and well combined.
6. Bake the Cake: Pour the batter into the prepared Bundt pan, smoothing the top with a spatula. Bake in the preheated oven for 1 hour and 20 minutes, or until a toothpick inserted into the center of the cake comes out clean. Let the cake cool in the pan for 10-15 minutes, then invert onto a wire rack to cool completely.
7. Prepare the Glaze: In a medium bowl, whisk together the powdered sugar, lemon juice, and 7 Up until smooth and pourable. If the glaze is too thick, add a little more 7 Up; if too thin, add more powdered sugar.
8. Glaze the Cake: Once the cake is completely cooled, drizzle the glaze over the top, allowing it to run down the sides. Let the glaze set for a few minutes before slicing and serving.
