Line a 10" X 15" jelly roll pan with heavy duty foil, then butter the foil or use non-stick spray; set aside.
Combine sugar, butter, milk, vanilla, and egg in large bowl. Beat at medium speed until creamy. Add the flour, baking powder, and salt and mix until well combined.
Spread the cookie dough onto the foil until even and smooth.
Bake for 10 to 12 minutes, until golden.
Using the foil, lift the cookie bars off the pan and set on a rack until completely cool.
Cream cheese filling:
Combine the cream cheese, powdered sugar, and vanilla extract in a small bowl and beat until smooth. Set aside.
Lemon Curd:
Combine the egg yolks, lemon juice, lemon zest, and granulated sugar in a small saucepan and cook on medium heat for 5 or 6 minutes, stirring constantly with a wooden spoon, until the mixture is thick and coats the spoon. Immediately remove from the heat and add the pieces of butter, one at a time, stirring them in and returning the pan to the heat, if the mixture cools too much. Strain the mixture through a fine mesh strainer into a small bowl and cover the surface with plastic wrap to keep a skin from forming. Set aside.
Cut bars into any shape or size, then spread with some of the cream cheese filling, then add a layer of lemon curd. Top with the fanned strawberries and scatter a few blueberries on top.