Add the granulated sugar, egg, and egg yolks to a small saucepan and whisk until well combined and pale yellow, about 1 minute. 

Add the lemon juice and lemon zest to the pan. Whisk to combine.

Set the pan over low heat and cook, whisking constantly for 4-5 minutes or until the curd has thickened enough to coat the back of a spoon. Make sure to keep whisking the whole time so the curd doesn’t scorch or curdle. 

Once the curd has thickened, remove it from the heat and whisk in the butter and vanilla.  

Once the butter has combined, pour the curd through a fine mesh sieve to remove the lemon zest and any bits of egg that may have scrambled. 

Place a piece of plastic wrap so that it is touching the surface of the lemon curd and then refrigerate the curd until it is completely cool, about 2 hours. 

Preheat your oven to 400 degrees F and spray 4 small tartlet pans with nonstick baking spray. 

Roll out your pie crust to ⅛ inch thick and cut out four circles that are ¼ inch larger than the base of your tart pans. 

Press each pie crust into a tart pan and then poke the bottom a few times with a fork. 

Place a piece of parchment paper over each crust and fill the center with pie weights or dried beans or rice. 

Bake for 10 minutes, then remove the pie weights and bake for an additional 5 minutes. 

When the crusts are golden brown, remove them from the oven and allow them to cool completely before filling. 

To assemble, remove a cooled crust from the tart pan and fill the center with lemon curd. Spread (or pipe) whipped cream on top and garnish with fresh raspberries. 

Serve immediately. Unfilled pie crusts can be kept in an airtight container at room temperature for up to three days. The lemon curd can be kept in an airtight container in the fridge for up to five days.