Preheat your oven to 325.
In a stand mixer or large mixing bowl, cream the butter and cream cheese together at a medium speed.
Slowly add in the sugar.
Once the sugar, butter, and cream cheese are creamed together, add in the eggs, but one egg at a time.
Slowly add the flour, just a little at a time. Then add in the pudding mix.
Pour in the lemon juice, then add in the lemon zest.
Add the vanilla extract, and mix the batter until smooth.
Grease and flour a bundt pan, then pour in the cake batter.
Let the cake bake for 1 hour and 25 minutes, OR until done.
Remove the cake from the oven, and let it cool before removing it from the pan.
Place the cake on a plate or cake server, and do not cut into it until it is completely cool.
Serve, and enjoy!