Mom's Cheesecake Cookie Bars: Silky

Instructions:

1. Cream the softened butter, granulated sugar, and brown sugar together until pale and fluffy.
2. Beat in the egg and vanilla extract.
3. Fold in the all-purpose flour, baking soda, salt, and semi-sweet chocolate chips until combined.
4. Press exactly half of the cookie dough firmly into the bottom of a parchment-lined 9x13 inch baking pan.
5. Beat the softened cream cheese and granulated sugar until completely smooth and devoid of lumps.
6. Add the egg and vanilla extract to the cream cheese mixture, mixing on low speed just until combined.
7. Pour the cheesecake filling over the cookie base and smooth the top with a spatula.
8. Drop small spoonfuls of the remaining cookie dough onto the top of the cheesecake layer, leaving small gaps between them.
9. Bake at 350°F (175°C) until the edges are deep golden brown and the center has a slight jiggle.
10. Allow the bars to cool completely at room temperature, then refrigerate for 2 hours before slicing with a serrated knife.