The filling is from the C Restaurant cookbook's baked lemon tarts recipe by its executive chef, Robert Clark. If you're looking at alternative lemon tart fillings, I do not recommend a lemon curd filling over this one, nor the lemon tart recipes made with extra egg yolks (you can identify those by the yolky color of the filling). This is an exquisitely bright, fresh, and creamy filling that is also more sophisticated, cheaper, and easier! It's a recipe that even kids can help with as mine did!
1/2 cup granulated sugar
1/3 cup fresh squeezed lemon juice
Grated zest of one lemon
1/3 cup heavy whipping cream
Whisk together the eggs, sugar, lemon zest, and juice. In a separate bowl that was chilled in the freezer, whip the cream at the highest speed, until it just holds its shape. Fold the whipped cream into the egg mixture.
Spoon it into small ramekins and bake at 275 degrees for 15 minutes. These can be served after they've cooled or can be served after longer refrigeration (3 hours will set it for sure, overnight works too - just cover them so they don't get an off-taste from your refrigerator). Top each serving with a few fresh blueberries and unsweetened coconut flakes (I love Let's Do Organic brand, found at Whole Foods) before serving.
To make the puff pastry tart shells, use two sheets of puff pastry dough (Pepperidge Farms is fine, Dufour is my favorite brand) and follow this procedure. After the shells are ready, spoon the filling in and bake them and refrigerate them the same as you would in the ramekins. Before serving, top them and warm them 15 seconds in the microwave. If you don't warm them, the dough is tasteless and stale like a croissant on the second day.
But before you decide on the puff pastry shells, let me explain why I prefer ramekins for this recipe: First, the dough shells are an unnecessary expenditure of money, time, and energy; second, the dough tastes better warm so it adds a complication to the serving time; third, the dough hides the taste of the coconut and dulls the fresh taste of the lemon filling; and fourth, the dough adds unnecessary calories. However, if you don't have enough ramekins to serve all your guests, don't want to do the dishes, or need finger-food desserts, then go the puff pastry route and try to cram in as much filling as possible. The more filling in each tart, the tastier it'll be. Enjoy!