Grate lemon zest into sugar and rub together to release oils
Combine butter, oil, and vanilla and mix until well combined
Add lemon sugar and whip on high speed until mixture turns pearly white
Add eggs one at a time, mixing between each addition
Add lemon extract, vanilla extract, buttermilk, flour, baking powder, and salt
Fold in poppy seeds and add a hint of yellow food coloring
Bake cakes
Make cream cheese frosting
Assemble cake, adding lemon curd between layers after chilling for 30 minutes
