In a saucepan over medium heat, combine 2 cups of fresh blueberries with sugar, stirring until the mixture begins to bubble.

In a small bowl, mix water and cornstarch until smooth, then add this to the pot. Cook for about 5 minutes, stirring gently until the compote thickens.

Once thickened, stir in remaining blueberries and set aside to cool to room temperature.

In a medium saucepan, whisk together egg yolks and sugar for Lemon Curd until smooth. Gradually add the lemon juice, then place the pan over medium heat, stirring constantly until thickened.

Remove from heat and whisk in cold butter and lemon zest, then cover and refrigerate to cool.

Choose either a homemade or pre-made tart shell ensuring it's cooled. Pour the lemon curd into the cooled tart shell.

Spoon blueberry compote evenly over the top, creating a layering effect. Refrigerate the assembled tart for at least one hour.

Serve each piece with a garnish of fresh mint or a dollop of whipped cream.