Preheat oven to 325 degrees F.
Grease a 10-inch Bundt cake pan.
In the bowl of a stand mixer or using a hand mixer, cream together the butter and sugar together until light and fluffy, around 20 minutes.
Add the flour, mixing until just combined.
Add the eggs one at a time, beating well after each addition.
Stir in the lemon extract.
Mix the 7Up into the batter.
Pour the mixture into a Bundt cake pan.
Bake for 60 to 75 minutes.
To make the glaze, beat the confectioner’s sugar, milk, and vanilla extract together in a mixing bowl until combined.
Pour glaze over warm 7Up Cake.
