Preheat oven to 450. Lightly grease a rimmed baking dish with non-stick cooking spray.
Lay the pie crust flat in the center of the baking sheet.
In a mixing bowl, toss together the sugar, cornstarch, cinnamon, allspice and pinch of salt. Gently toss in the thinly sliced apples. Place the mixture into the middle of the pie crust.
Fold over the edges of the pie crust to "wrap the apples." Brush the top of the crust with water and sprinkle with 1 to 2 tsp sugar.
Bake in the preheated oven for 15 minutes. Add the chopped pecans and bake another 5 to 10 minutes.
Let cool and serve Apple Crostata with whipped cream topping.