For the shortbread crust:Ingredients: 1/2 c. sugar3/4 c. butter, softened1 egg1/2 tsp. vanilla2 c. flour1/4 tsp. saltPreheat oven to 350 degrees. Lightly grease a 9x13 pan. Using the mixer, cream butter and sugar. Beat in egg and vanilla. Working at a low speed, gradually add in flour and salt until mixture is crumbly.Pour crumbly dough into the prepared pan and press into an even layer. Bake for 20-25 minutes until base is set and edges are lightly...