Preheat the oven to 350 degrees. Lightly grease a 9" square pan.

Crust: Beat butter to soften, then mix in remaining "crust" ingredients until the dough holds together when you squeeze it. Press it into the bottom and 1/2" up the sides of the prepared pan. Prick the dough all over with a fork. Bake the crust for 22-26 minutes, until it's golden. Reduce temperature to 300 degrees.

Filling: Whisk together the eggs, lemon juice, lemon zest and raspberry puree. Whisk the cornstarch with the sugar and salt, then stir into juice mixture. Pour filling over the baked crust. Bake the bars in preheated 300 degree over to 30-35 minutes, until the middle is set. Cool before topping.

Topping: Melt the white chocolate over low heat. Stir in the cream and corn syrup. Spread over the cooled squares. Decorate with shaved white chocolate, if desired. When the topping is set, slice into squares. Refrigerate any uneaten squares.