For the crust: In a bowl, cream butter with electric mixture until light. Gradually add maple syrup and vanilla.

Combine flour and salt, then gradually add to cream mixture, working in with a wooden spoon.

Using floured hands, pat into 13×9 inch baking dish and smooth out with a can or bottle. Refrigerate until needed.

Preheat oven to 400 degrees. With an electric mixer, beat cream cheese in bowl until light and fluffy. Beat in sour cream, then eggs, one at a time. Gradually beat in maple syrup, then vanilla and lemon juice.

Sprinkle chocolate chips evenly over prepared crust. Slowly pour on cheese mixture.

Bake in preheated oven 15 minutes, then reduce oven temperature to 350 degrees and bake 30 minutes longer, until cake is puffy and develops cracks on top.

Cool on wire rack, then cover and chill. When well chilled, cut into bars.