Prepare the crust: In a bowl, mix graham cracker crumbs and melted butter. Press the mixture firmly into the bottom of an 8x8-inch baking dish lined with parchment paper.
Make the filling: In a blender or food processor, combine the pink beans, cream cheese, sugar, vanilla extract, egg and lemon juice (if using). Blend until smooth and creamy.
Assemble and bake: Pour the filling over the crust and smooth it out with a spatula. Bake for about 20 minutes or until the center is set but still slightly jiggly.
Cool and serve: Allow the bars to cool, then refrigerate for at least 10 minutes before slicing into squares.