Preheat your oven to 350°F (175°C). Roll out your tart shells or pastry dough, fitting them into tart pans, then pierce the bottoms with a fork. Blind bake the shells for 10-15 minutes until lightly golden.

In a saucepan over medium heat, combine sugar and a splash of water. Stir gently until dissolved and allow to bubble until it turns deep golden brown, about 8-10 minutes. Carefully whisk in heavy cream until smooth, then set aside to cool slightly.

In a mixing bowl, combine the pumpkin puree and pumpkin spice, stirring until well blended. Spoon the spiced mixture into each baked tart shell, filling them about three-quarters full. Pour the warm caramel sauce over the pumpkin.

Transfer the filled tarts back into the oven and bake for an additional 25 minutes. You'll know they're done when the pumpkin filling is set and slightly puffed.

Once baked, remove the tarts from the oven and let them cool on a wire rack for at least 30 minutes to enhance flavors and help the caramel set.