In the bowl of a food processor, cream together the butter and brown sugar. Set aside 1 tbsp (15 ml) of the beaten eggs to brush over the pie, then add the remaining eggs to the food processor. Sprinkle with the salt and process until the eggs are well incorporated, about 5 seconds. Scrape down the bowl. Add a third of the flour, then process until well incorporated, about 10 seconds. Scrape down the bowl, then add another third of the flour, and process for another 10 seconds. Scrape down the bowl. At this point, the mixture will start gathering together.
Add the remaining flour and process until the dough fully comes together, stopping to scrape down the bowl as needed. When ready, the dough looks uniform in color and it is soft and holds together when pressed. The texture should be very similar to Play-Doh.
Transfer the dough to a bowl, cover with plastic wrap, and rest at room temperature while you prepare the filling.
FOR THE DUTCH SPICE MIX
Mix all the spices together and store in an airtight spice bottle or glass jar.
FOR THE FILLING
Peel and core the apples, then cut them into bite-size pieces. In a large bowl, mix the apples with the orange and lemon zest, lemon juice, brown sugar, spices, cornstarch, and the liqueur, raisins, and walnuts, if using. Set aside.
Set aside 1/4 of the crust mixture to create the topping. Add about half of the remaining crust mixture to the springform pan and press down to cover the entire bottom of the pan in an even layer.
Pick up chunks of the remaining crust and roughly press it against the sides of the springform pan until you've fully covered it. Now press it more carefully to create a smooth edge, making sure the sides seamlessly connects with the bottom crust.
Transfer the apple filling to the crust and gently press it down flatten it. Spread the remaining of the crust mixture all over the apples. You'll need to first dot the crust mixture in chunks over the apple surface, then spread and smooth it down using your fingers or a spatula.
Brush the reserved eggs over the top of the pie, then sprinkle with 2 tbsp (30 ml) brown sugar and extra chopped walnuts, if desired.
Set the springform pan over a baking sheet (some juices may leak out during baking), then bake for 75 to 85 minutes. Check on the pie after 45 minutes: if it's golden brown, loosely cover it with aluminum foil to prevent it from getting too dark. To check whether the Dutch apple pie is done, use a bamboo skewer or a small, very sharp knife to poke through the pie. If the pie is done, you’ll easily pierce through the apples. If you feel they’re still a bit crunchy, continue baking until they're soft.
Transfer the Dutch apple pie to a cooling rack and let it cool completely. This will take at least 3 hours. The pie slices more easily if it has rested overnight. Carefully unmold the Dutch apple pie, running a sharp knife around the pie if needed, and use a serrated knife to slice into pieces.
HOW TO SERVE DUTCH APPLE PIE
Serve at room temperature garnished with whipped cream, or warm, topped with vanilla bean gelato or ice cream.