In a medium saucepan, combine 2 cups of fresh blueberries with ½ cup of sugar over medium heat. Stir gently for about 2 minutes until the sugar dissolves. In a small bowl, mix 1 tablespoon of cornstarch with 1 ounce of water until smooth, then add to the berries. Cook for 5 minutes, stirring continuously until thickened. Remove from heat and let it cool completely.

While the blueberry compote cools, prepare the lemon curd. In a saucepan, whisk together 6 egg yolks and 1 cup of sugar. Gradually add ½ cup of fresh lemon juice, stirring continuously. Cook over medium heat for about 10 minutes until it thickens. Remove from heat and stir in 4 ounces of cold butter and 1 tablespoon of grated lemon zest until smooth. Chill in the refrigerator until set.

Preheat your oven to 350°F (175°C). If making a homemade tart shell, combine 1 ½ cups of flour, ½ cup of powdered sugar, and ½ cup of cold butter in a bowl. Mix until crumbly, then add 1 egg to form a dough. Press the dough into a tart pan and prick the bottom with a fork. Bake for 20 minutes until pale golden. Allow the tart shell to cool completely.

Once the tart shell is cool, pour the lemon curd into the shell, spreading it evenly with a spatula.

Carefully spoon the cooled blueberry compote on top of the lemon curd without mixing the two layers.

After assembly, chill the tart in the refrigerator for at least 2 hours.

To serve, slice the tart into wedges. Pairs beautifully with whipped cream or vanilla ice cream.