Preheat your oven to 350°F (175°C) and line an 8x8-inch baking dish with parchment paper.

In a mixing bowl, combine graham cracker crumbs, flour, granulated sugar, and salt. Pour in melted butter and mix until resembling wet sand.

Set aside one-third of the crumb mixture for topping and press the remaining two-thirds into the bottom of the prepared baking dish.

In a separate bowl, beat cream cheese until smooth. Gradually mix in sugar, then add eggs one at a time. Fold in lemon zest, juice, and vanilla.

Pour the filling over the crust and sprinkle the reserved crumb mixture on top. Bake for 30–35 minutes until the center is set but slightly jiggly.

Let the bars cool to room temperature for about 1 hour, then refrigerate for at least 3 hours before serving.