1-In a small sauce pan combine egg yolks, sugar, lemon zest, and lemon juice. Heat over medium heat for 5-7 minutes, be sure to stir mixture almost continuously.
2- Once mixture becomes thick enough that it sticks to your spoon almost like a syrup remove from heat and stir in one tablespoon of butter at a time until all 4 tablespoons are complete dissolved.
3- Cover with plastic wrap and refrigerate for 2 hours at least. You can store it for 2 days at the most.
Side note: if you lay the plastic wrap directly against the lemon curd while it sets you won't get that weird skin curds and pudding always get while they set typically. It'll make it easier to mix and spread on your cake later.
1- In a large mixing bowl sift cake flour, salt and baking powder together, set aside.
4In another large mixing bowl cream butter, your sugar and lemon zest together until completely creamy.
5In a measuring cup pour of 1 cup of cream, mix it with vanilla extract and lemon juice, set aside.
6Add eggs to butter mixture one egg at a time until completely incorporated.
7Add flour to creamed butter mixture in thirds, adding cream mixture to batter in between adding your flour.
In all you will interchange adding three batches of flour and two batches of the cream. Completely incorporate, but do not over mix.
8Pour out into pans and bake for 21 minutes, or until a tooth pick comes out just barely clean.
Cool cakes completely on wire wrack.
1- In a mixing bowl cream butter and cream cheese until fluffy. Gradually add confectioner's sugar until completely incorporated.
2- Add vanilla and lemon juice and whip until smooth.
3- Add food coloring is desired. Set aside.
1- Core each cupcake with a pairing knife or use a cupcake corer. Do not make hole more than 3/4 inch deep.
2- Spoon a bit of the lemon curd into each cupcake hole.
3- Frost cakes as desired with lemon cream cheese frosting.