Preheat your oven to 350°F (175°C). Make sure your cream cheese is soft and your eggs are at room temperature.
Make the filling by beating the softened cream cheese in a large bowl until smooth. Add eggs, 3/4 cup sugar, 1 teaspoon vanilla, and half the lemon zest. Beat until completely smooth and creamy, about 2-3 minutes.
Pour into crust and spread the cream cheese mixture evenly in your graham cracker crust.
Bake the pie for 30-35 minutes, until the edges are set and the center is just slightly jiggly.
Make the topping while the pie bakes. Mix sour cream, 1/4 cup sugar, 1 teaspoon vanilla, and remaining lemon zest in a small bowl.
Cool briefly - Remove pie from oven and let it cool for 5 minutes.
Increase oven temperature to 450°F (232°C).
Add topping by spreading the sour cream mixture evenly over the pie.
Final bake - Return to oven for 5 minutes only.
Cool completely at room temperature, then refrigerate for at least 4 hours or overnight.
Serve with fresh lemon slices or berries if desired.