Preheat oven to 350 degrees (F). Light spray a 9" pie plate with non-stick baking spray; set aside.
In a large bowl add the melted butter, brown sugar, and granulated sugar; beat well until combined. Beat in the egg, egg yolks, and vanilla. Add in the flour, cornstarch, and salt and mix until just combined. Be sure not to over mix here! Fold in the chocolate chips and toffee bits. Spread the mixture into the prepared pie plate and bake for 35 to 40 minutes, or until the top is golden brown, the edges are completely set, and the center of the pie is only slightly jiggly. Place pie on a wire rack to cool for at least one hour before slicing and serving.