Follow these straightforward steps to make your No-Bake Lemon Cheesecake Bars:

1. Prepare the Pan: Line an 8×8-inch square baking dish with parchment paper, leaving some overhang for easy removal.
2. Make the Crust: In a mixing bowl, combine graham cracker crumbs, melted butter, and granulated sugar. Stir until well mixed.
3. Pat the Crust: Press the mixture evenly into the bottom of the prepared baking dish. Use the back of a spoon to flatten.
4. Chill the Crust: Place the crust in the refrigerator while you prepare the filling.
5. Blend the Filling: In a large bowl, beat softened cream cheese until smooth. Add powdered sugar, sour cream, lemon juice, lemon zest, and vanilla extract, mixing until well combined.
6. Whip the Cream: In a separate bowl, whip heavy cream until stiff peaks form. Carefully fold the whipped cream into the cream cheese mixture until no streaks remain.
7. Spread the Filling: Pour the filling over the chilled crust, smoothing the top with a spatula.
8. Chill Again: Cover and refrigerate for at least 4 hours or until set.
9. Slice and Serve: Once set, lift the bars out of the pan using the parchment overhang. Cut into squares and serve.