In a medium bowl, whisk together the flour, baking powder, and salt. Set aside.

In a large bowl, cream together the softened butter, vegetable oil, and sugar using an electric mixer on medium speed. Beat until the mixture is light and fluffy, about 3-4 minutes.

Add the eggs, one at a time, beating well after each addition. Then add the vanilla extract and lemon extract. Mix until fully combined.

Gradually add the dry ingredients to the wet mixture in 3 parts, alternating with the 7UP and sour cream. Begin and end with the dry ingredients. Mix on low speed to combine, and then increase the speed to medium and mix until smooth. Be careful not to over-mix. Fold in the lemon zest.

Pour the batter into the prepared pan and spread evenly. Bake for 55 minutes or until a toothpick inserted into the center of the cake comes out clean.

Let the cake cool in the pan for about 10 minutes. Then invert the cake onto a wire rack to cool completely.

While the cake cools, whisk together the confectioners' sugar, 7UP, lemon juice, and vanilla extract in a small bowl. The glaze should be smooth and pourable.

Once the cake has cooled completely, drizzle the glaze evenly over the top of the cake, allowing it to drip down the sides. Let the glaze set for 10-15 minutes before serving.