Spray a 9-inch tart pan with non-stick baking spray and preheat oven to 350°F (176°C).

Add the graham cracker crumbs and sugar to a medium sized bowl and stir to combine. Add the melted butter and stir until well combined.

Pour the mixture into the tart pan and press the crumbs into the bottom and up the sides of the pan. Pack it firmly. Use a measuring cup or glass with sharp corners and straight edges to help and use your fingers for the sides of the pan.

Bake for 7 minutes, then remove from oven and set aside.

Add the lemon juice and sweetened condensed milk to a medium sized bowl and stir until well combined. Set aside.

In a large mixer bowl, beat the lemon zest and egg yolks on high speed until pale yellow.

Add the sweetened condensed milk mixture to the egg mixture and mix until well combined.

Pour the filling into the crust and bake for 15-17 minutes. The edges should be set and the center should jiggle a little when the tart is moved.

Cool at room temperature for about 30 minutes, then refrigerate for 4-6 hours, or until completely cool and firm.

To make the whipped cream, add the heavy whipping cream, powdered sugar and vanilla extract and whip on high speed until stiff peaks form.

Pipe the whipped cream on top of the tart. I used Ateco tip 844 to create a rosette design. Cover and refrigerate tart until ready to serve. Best if eaten within 3-4 days.