Preheat your oven to 350°F (175°C). Grease a 9x13-inch baking pan or line it with parchment paper for easy removal.
In a large mixing bowl, cream together the butter and sugar until light and fluffy. Add the eggs and vanilla extract, mixing well.
Gradually add the flour and salt to the butter mixture, stirring until combined. The dough will be thick.
Reserve about 1½ cups of the dough for the topping. Press the remaining dough evenly into the prepared pan to form the crust.