Make the crust:
1. In a medium bowl, cream the butter and powdered sugar until you obtain a smooth texture. Add the egg, vanilla extract, and flour. Mix until smooth and form a ball.

2. Flour your work surface and dust the dough with flour. Using a rolling pin, roll into a circle 12 inches (30 cm) in diameter, turning and adding more flour as necessary so the dough doesn’t stick. Transfer the dough to a cast iron or a skillet parchment-lined baking sheet and refrigerate 15 to 30 mins.

Assemble the tart
1. Take the dough from the fridge. Arrange the blueberries in the center of the pastry, within 3 inches of the edge. Sprinkle the blueberries with another tablespoon of brown sugar. Fold the edges of the dough over the blueberries in a free-form fashion, working your way around and creating pleats as you go. Patch up any tears by pinching a bit of dough from the edge.

2. Using a pastry brush, brush the crust evenly with jam. Sprinkle brown sugar over the top of the crust. Refrigerate the assembled tart in the fridge for 15 to 20 minutes. Meanwhile, preheat the oven to 350°F (180ºC) and set an oven rack in the center position.

Baking
1. Bake for 30 to 45 minutes, or until the blueberries are tender and the crust is golden and cooked through. It’s okay if some of the juices leak from the tart onto the pan. Transfer the cast iron skillet or baking sheet to a rack and let cool.

2. Transfer the tart to a serving plate or cutting board. Slice and serve warm or at room temperature. Enjoy!

• • The dough can be made up to 3 days in advance and refrigerated. Allow it to sit at room temperature for about 15 minutes before rolling, or until pliable.
  • The tart is freezer-friendly: Place the baking sheet in the freezer until the tart is frozen, then wrap tightly and keep in the freezer for up to 3 months. Bake directly from the freezer.