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

In a medium bowl, combine flour, 1/2 cup sugar, salt, and 1 tablespoon lemon zest. Stir in melted butter until a crumbly dough forms.

Press two-thirds of the crumb mixture firmly into the bottom of the prepared pan to form the base.

Par-bake the crust for 10 minutes, then remove from oven.

In a large bowl, beat the softened cream cheese and remaining 1/2 cup sugar until smooth and aerated.

Whisk in the egg, lemon juice, remaining 1 tablespoon lemon zest, and vanilla extract until fully incorporated.

Spread the cream cheese filling evenly over the par-baked crust.

Sprinkle the remaining one-third of the crumb mixture evenly over the filling layer.

Bake for 25 to 30 minutes until the edges are golden brown and the cheesecake center is set.

Cool completely at room temperature, then refrigerate for a minimum of 2 hours to ensure clean slicing.