Prepare the Filling: In a pan over medium-high heat, combine water, cornstarch, brown sugar, white sugar, cinnamon, nutmeg, cardamom, and salt. Stir until thickened, about 5 minutes. Then add sliced apples and cook for another 10 minutes until tender.

Form the Crusts: Roll out the pie crust and cut out 3-inch circles. Carefully line a greased muffin pan with these crusts, gently folding where necessary to fit them snugly.

Fill Crusts: Spoon the warm apple filling into each prepared crust, filling them about ¾ full to allow room for the crumb topping.

Add Crumb Topping: In a bowl, mix flour, butter, and sugar until crumbly. Sprinkle this mixture evenly over each mini pie.

Bake: Place your muffin pan in the oven and bake at 350°F (175°C) for 16-17 minutes, or until the tops are golden brown and the filling is bubbling.

Cool and Serve: Let the mini pies cool slightly for about 5 minutes. Serve them warm with whipped cream and caramel sauce.