Lemon Cake

2 1/2 cups (285g) cake flour
1 1/2 cups (300g) granulated sugar
1/2 teaspoon (3g) salt
2 1/2 teaspoons baking powder
1 1/2 sticks (12 T) (169g) unsalted butter, softened ( do not soften in the microwave) you can cut into 1/4 inch slices onto waxed paper to soften more quickly
4 large eggs, room temperature
1 1/4 cup (302g) milk
2 Tablespoons (18g) vegetable oil
2 teaspoons (8g) lemon extract
zest of 2 lemons - best done with a microplane, just the yellow of the lemon

Lemon Cream Cheese Frosting:

3 (8 ounces)(678g) cream cheese .....I used full fat cream cheese
1/4 to 1/2 cup (66g) lemon curd -see clarification below.
3 cups (345g) powdered sugar.......measure then sift

Lemon Curd:

3/4 cup sugar
1/4 cup cornstarch
1 cup water
2 large egg yolks, lightly beaten
2 Tablespoons butter
1 Tablespooon grated lemon zest
4 Tablespoons fresh lemon juice