Grease a large casserole dish (I used a 13 x 10-inch dish) with butter or shortening.
Put the gingersnap cookies in a food processor and pulse until they are finely ground.
Mix with the melted butter and press into the prepared casserole dish, using the palm of your hand or the bottom of a measuring cup. Set aside.
Place the egg yolks in a large mixing bowl and beat in the powdered sugar until the mixture has doubled.
Add the mascarpone cheese and beat until blended. Add the pumpkin puree, spices, salt, and Amaretto or Disaronno and beat on low speed until incorporated.
In a stainless steel or glass bowl, beat the heavy whipping cream until stiff peaks form and it holds its shape. Fold the cream into the pumpkin mixture and set aside.
Pour half of the pumpkin mixture onto of the gingersnap crust and sprinkle half of the crumbled meringues on top. Drizzle with the salted caramel.
Pour the rest of the pumpkin mixture on top, sprinkle with the rest of the crumbled meringues, and drizzle with caramel sauce again.
Put the dish in the freezer, making sure it lays flat. Freeze overnight before cutting into squares. Store in an airtight container in the freezer.
I always use make my own homemade pumpkin puree because I don't like canned pumpkin:
Make sure to grease the bottom of the casserole dish. I didn’t the first time I made this and the bars were hard to get out without leaving behind the crust.